A   CUSIP   is a nine-character alphanumeric code that identifies a North American financial security for the purposes of facilitating clearing and settlement of trades. The CUSIP was adopted as an American National Standard under Accredited Standards X9.6.

Task
CUSIP
You are encouraged to solve this task according to the task description, using any language you may know.
This page uses content from Wikipedia. The original article was at CUSIP. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)



Task

Ensure the last digit   (i.e., the   check digit)   of the CUSIP code (the 1st column) is correct, against the following:

  •   037833100       Apple Incorporated
  •   17275R102       Cisco Systems
  •   38259P508       Google Incorporated
  •   594918104       Microsoft Corporation
  •   68389X106       Oracle Corporation   (incorrect)
  •   68389X105       Oracle Corporation


Example pseudo-code below.
algorithm Cusip-Check-Digit(cusip) is
   Input: an 8-character CUSIP

   sum := 0
   for 1 ≤ i ≤ 8 do
      c := the ith character of cusip
      if c is a digit then
         v := numeric value of the digit c
      else if c is a letter then
         p := ordinal position of c in the alphabet (A=1, B=2...)
         v := p + 9
      else if c = "*" then
         v := 36
      else if c = "@" then
         v := 37
      else if' c = "#" then
         v := 38
      end if
      if i is even then
         v := v × 2
      end if

      sum := sum + int ( v div 10 ) + v mod 10
   repeat
   
   return (10 - (sum mod 10)) mod 10
end function
See related tasks


Translation of: Python
F cusip_check(=cusip)
   I cusip.len != 9
      X.throw ValueError(‘CUSIP must be 9 characters’)

   cusip = cusip.uppercase()
   V total = 0
   L(i) 0.<8
      V v = 0
      V c = cusip[i]
      I c.is_digit()
         v = Int(c)
      E I c.is_alpha()
         V p = c.code - ‘A’.code + 1
         v = p + 9
      E I c == ‘*’
         v = 36
      E I c == ‘@’
         v = 37
      E I c == ‘#’
         v = 38

      I i % 2 != 0
         v *= 2

      total += v I/ 10 + v % 10
   V check = (10 - (total % 10)) % 10
   R String(check) == cusip.last

V codes = [‘037833100’,
           ‘17275R102’,
           ‘38259P508’,
           ‘594918104’,
           ‘68389X106’,
           ‘68389X105’]
L(code) codes
   print(code‘: ’(I cusip_check(code) {‘valid’} E ‘invalid’))
Output:
037833100: valid
17275R102: valid
38259P508: valid
594918104: valid
68389X106: invalid
68389X105: valid
*        CUSIP                     07/06/2018
CUSIP    CSECT
         USING  CUSIP,R13          base register
         B      72(R15)            skip savearea
         DC     17F'0'             savearea
         SAVE   (14,12)            save previous context
         ST     R13,4(R15)         link backward
         ST     R15,8(R13)         link forward
         LR     R13,R15            set addressability
         LA     R6,1               i=1
       DO WHILE=(C,R6,LE,=F'6')    do i=1 to 6
         LR     R1,R6                i
         MH     R1,=H'9'             *9
         LA     R4,T-9(R1)           @t(i)
         MVC    X,0(R4)              x=t(i)
         SR     R10,R10              w=0
         LA     R7,1                 j=1
       DO WHILE=(C,R7,LE,=F'8')      do j=1 to 8
         LA     R14,X-1                x
         AR     R14,R7                 j
         MVC    Y(1),0(R14)            y=substr(x,j,1)
         LA     R9,L'XX                z=length(xx)
         LA     R8,1                   k=1
       DO WHILE=(C,R8,LE,=A(L'XX))     do k=1 to length(xx)
         LA     R4,XX-1                  xx
         AR     R4,R8                    k
         MVC    C(1),0(R4)               c=substr(xx,k,1)
       IF CLC,Y(1),EQ,C THEN             if y=c then
         LR     R9,R8                      k
         BCTR   R9,0                       z=k-1
       ENDIF    ,                        endif
         LA     R8,1(R8)                 k++
       ENDDO    ,                      enddo k
         LR     R4,R7                  j
         LA     R1,2                   2
         SRDA   R4,32                  ~
         DR     R4,R1                  j/2=0
       IF LTR,R4,Z,R4 THEN             if j//2=0 then
         AR     R9,R9                    z=z+z
       ENDIF    ,                      endif
         LR     R4,R9                  z
         LA     R1,10                  10
         SRDA   R4,32                  ~
         DR     R4,R1                  r4=z//10 ; r5=z/10
         AR     R10,R5                 w+z/10
         AR     R10,R4                 w=w+z/10+z//10
         LA     R7,1(R7)               j++
       ENDDO    ,                    enddo j
         LR     R4,R10               w
         LA     R1,10                10
         SRDA   R4,32                ~
         DR     R4,R1                w/10
         LA     R2,10                10
         SR     R2,R4                10-w//10
         SRDA   R2,32                ~
         DR     R2,R1                /10
         STC    R2,U                 u=(10-w//10)//10
         OI     U,X'F0'              bin to char
       IF CLC,U,EQ,X+8 THEN          if u=substr(x,9,1) then
         MVC    OK,=CL3' '             ok=' '
       ELSE     ,                    else
         MVC    OK,=C'n''t'            ok='n''t'
       ENDIF    ,                    endif
         MVC    PG+6(9),X            output x
         MVC    PG+18(3),OK          output ok
         XPRNT  PG,L'PG              print
         LA     R6,1(R6)             i++
       ENDDO    ,                  enddo i
         L      R13,4(0,R13)       restore previous savearea pointer
         RETURN (14,12),RC=0       restore registers from calling sav
XX       DC     CL39'0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ*@#'
U        DS     CL1
Y        DS     CL1
C        DS     CL1
T        DC     CL9'037833100',CL9'17275R102',CL9'38259P508'
         DC     CL9'594918104',CL9'68389X106',CL9'68389X105'
X        DS     CL9
OK       DS     CL3
PG       DC     CL80'CUSIP ......... is... valid'
         YREGS
         END    CUSIP
Output:
CUSIP 037833100 is    valid
CUSIP 17275R102 is    valid
CUSIP 38259P508 is    valid
CUSIP 594918104 is    valid
CUSIP 68389X106 isn't valid
CUSIP 68389X105 is    valid
INCLUDE "D2:CHARTEST.ACT" ;from the Action! Tool Kit

BYTE FUNC Verify(CHAR ARRAY code)
  BYTE i,c,v
  CARD sum

  IF code(0)#9 THEN
    RETURN (0)
  ELSEIF IsDigit(code(1))=0 THEN
    RETURN (0)
  FI

  sum=0
  FOR i=2 TO code(0)
  DO
    c=code(i)
    IF IsDigit(c) THEN
      v=c-'0
    ELSEIF IsAlpha(c) THEN
      v=ToUpper(c)-'A+10
    ELSEIF c='* THEN
      v=36
    ELSEIF c='@ THEN
      v=37
    ELSEIF c='# THEN
      v=38
    ELSE
      RETURN (0)
    FI

    IF (i&1)=0 THEN
      v==*2
    FI

    sum==+v/10+v MOD 10
  OD

  v=(10-(sum MOD 10)) MOD 10
  IF v#code(1)-'0 THEN
    RETURN (0)
  FI
RETURN (1)

PROC Test(CHAR ARRAY code)
  Print(code)
  IF Verify(code) THEN
    PrintE(" is valid")
  ELSE
    PrintE(" is invalid")
  FI
RETURN

PROC Main()
  Put(125) PutE() ;clear the screen
  Test("037833100")
  Test("17275R102")
  Test("38259P508")
  Test("594918104")
  Test("68389X106")
  Test("68389X105")
RETURN
Output:

Screenshot from Atari 8-bit computer

037833100 is valid
17275R102 is valid
38259P508 is valid
594918104 is valid
68389X106 is invalid
68389X105 is valid
with Ada.Text_IO;

procedure Cusip_Test is
   use Ada.Text_IO;

   subtype Cusip is String (1 .. 9);

   function Check_Cusip (Code : Cusip) return Boolean is
      Sum : Integer := 0;
      V   : Integer;

   begin
      for I in Code'First .. Code'Last - 1 loop
         case Code (I) is
            when '0' .. '9' =>
               V := Character'Pos (Code (I)) - Character'Pos ('0');
            when 'A' .. 'Z' =>
               V := Character'Pos (Code (I)) - Character'Pos ('A') + 10;
            when '*' => V := 36;
            when '@' => V := 37;
            when '#' => V := 38;
            when others => return False;
         end case;

         if I mod 2 = 0 then
            V := V * 2;
         end if;

         Sum := Sum + V / 10 + (V mod 10);
      end loop;

      return (10 - (Sum mod 10)) mod 10 =
        Character'Pos (Code (Code'Last)) - Character'Pos ('0');
   end Check_Cusip;

   type Cusip_Array is array (Natural range <>) of Cusip;

   Test_Array : Cusip_Array :=
     ("037833100",
      "17275R102",
      "38259P508",
      "594918104",
      "68389X106",
      "68389X105");
begin
   for I in Test_Array'Range loop
      Put (Test_Array (I) & ": ");
      if Check_Cusip (Test_Array (I)) then
         Put_Line ("valid");
      else
         Put_Line ("not valid");
      end if;
   end loop;
end Cusip_Test;
Output:
037833100: valid
17275R102: valid
38259P508: valid
594918104: valid
68389X106: not valid
68389X105: valid
Translation of: Modula-2
COMMENT CUSIP;

BEGIN

COMMENT Defined procedures peek, sloc, tlen, so linking is not necessary;

INTEGER PROCEDURE peek(a);
  VALUE a; INTEGER a; ioc(36);

INTEGER PROCEDURE sloc(s);
  STRING s; ioc(55);

INTEGER PROCEDURE tlen(a);
  VALUE a; INTEGER a; ioc(54);

INTEGER PROCEDURE checkdigit(cusip);
COMMENT Check digit;
  STRING cusip;
BEGIN
  INTEGER sum, v, ilast, i;
  INTEGER c, loc;
  BOOLEAN checkneeded;
  i := 0;
  sum := 0;
  loc := sloc(cusip);
  ilast := tlen(loc) - 1;
  checkneeded := TRUE;
  WHILE (i < ilast) AND checkneeded DO
  BEGIN
    c := peek(loc + i);
    COMMENT Codes of non-alphanumeric chars: 
      42 of "*", 64 of "@", 35 of "#";
    IF (&0 <= c) AND (c <= &9) THEN
      v := c - &0 
    ELSE IF (&A <= c) AND (c <= &Z) THEN
      v := c - &A + 10
    ELSE IF c = 42 THEN 
      v := 36
    ELSE IF c = 64 THEN 
      v := 37
    ELSE IF c = 35 THEN
      v := 38
    ELSE
    BEGIN
      checkdigit := -1;
      checkneeded := FALSE;
    END;
    IF checkneeded THEN
    BEGIN
      IF i MOD 2 = 1 THEN
        v := 2 * v;
      IF i <= 7 THEN
        sum := sum + entier(v / 10) + (v MOD 10);
      i := i + 1
    END;
  END;
  IF checkneeded THEN
  BEGIN
    IF i # 8 THEN
      checkdigit := -1
    ELSE
      checkdigit := (10 - sum MOD 10) MOD 10;
  END;  
END;

BOOLEAN PROCEDURE isvalid(cusip);
  STRING cusip;
BEGIN
  INTEGER check;
  check := checkdigit(cusip);
  IF check < 0 THEN
    isvalid := FALSE
  ELSE
    isvalid := (peek(sloc(cusip) + 8) = &0 + check)
END;

PROCEDURE writeverdict(cusip);
  STRING cusip;
BEGIN
  text(1, cusip);
  IF isvalid(cusip) THEN
    text(1, " : Valid")
  ELSE
    text(1, " : Invalid");
  skip(1);
END;

text(1, "CUSIP       Verdict");
skip(1);
writeverdict("037833100");
writeverdict("17275R102");
writeverdict("38259P508");
writeverdict("594918104");
writeverdict("68389X106");
writeverdict("68389X105");
END FINISH
Output:
CUSIP       Verdict
037833100 : Valid
17275R102 : Valid
38259P508 : Valid
594918104 : Valid
68389X106 : Invalid
68389X105 : Valid
BEGIN # validate CUSIP codes #

    # returns TRUE if cusip string is a valid CUSIP code, FALSE otherwise #
    OP   ISCUSIP = ( STRING cusip string )BOOL:
         IF UPB cusip string - LWB cusip string /= 8
         THEN FALSE # CUSIP code is not 9 characters long #
         ELSE       # CUSIP code has the correct length #

            # returns the base 39 digit corresponding to a character of a CUSIP code #
            PROC cusip digit = ( CHAR c char )INT:
                 IF   STRING cusip digits = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ*@#"[ AT 0 ];
                      INT digit := 0;
                      char in string( c char, digit, cusip digits )
                 THEN digit
                 ELSE -999 # invalid digit #
                 FI # cusip digit # ;

            []CHAR cusip = cusip string[ AT 1 ];
            INT sum := 0;
            INT check digit = cusip digit( cusip[ UPB cusip ] );
            FOR c pos TO UPB cusip - 1 DO
                INT digit := cusip digit( cusip[ c pos ] );
                IF NOT ODD c pos THEN digit *:= 2 FI;
                sum +:= ( digit OVER 10 ) + ( digit MOD 10 )
            OD;
            ( 10 - ( sum MOD 10 ) ) MOD 10 = check digit
         FI # is cusip # ;

    # task test cases #

    PROC test cusip = ( STRING cusip )VOID:
         print( ( cusip, IF ISCUSIP cusip THEN " valid" ELSE " invalid" FI, newline ) );

    test cusip( "037833100" );
    test cusip( "17275R102" );
    test cusip( "38259P508" );
    test cusip( "594918104" );
    test cusip( "68389X106" );
    test cusip( "68389X105" )
END
Output:
037833100 valid
17275R102 valid
38259P508 valid
594918104 valid
68389X106 invalid
68389X105 valid

Based on Algol 68

begin    % returns true if cusip is a valid CUSIP code %
    logical procedure isCusip ( string(9) value cusip ) ;
    begin
        % returns the base 39 digit corresponding to a character of a CUSIP code %
        integer procedure cusipDigit( string(1) value cChar ) ;
            if      cChar >= "0" and cChar <= "9" then ( decode( cChar ) - decode( "0" ) )
            else if cChar >= "A" and cChar <= "Z" then ( decode( cChar ) - decode( "A" ) ) + 10
            else if cChar  = "*"                  then   36
            else if cChar  = "@"                  then   37
            else if cChar  = "#"                  then   38
            else    % invalid digit %                  -999 ;

        integer checkDigit, sum;
        checkDigit := cusipDigit( cusip( 8 // 1 ) );
        for cPos := 1 until 8 do begin
            integer   digit;
            digit := cusipDigit( cusip( ( cPos - 1 ) // 1 ) );
            if not odd( cPos ) then digit := digit * 2;
            sum := sum + ( digit div 10 ) + ( digit rem 10 )
        end for_cPos ;
        ( ( 10 - ( sum rem 10 ) ) rem 10 ) = checkDigit
    end isCusip ;

    begin % task test cases %
        procedure testCusip ( string(9) value cusip ) ;
            write( s_w := 0, cusip, if isCusip( cusip ) then " valid" else " invalid" );

        testCusip( "037833100" );
        testCusip( "17275R102" );
        testCusip( "38259P508" );
        testCusip( "594918104" );
        testCusip( "68389X106" );
        testCusip( "68389X105" )
    end testCases
end.
Output:
037833100 valid
17275R102 valid
38259P508 valid
594918104 valid
68389X106 invalid
68389X105 valid
use AppleScript version "2.4"
use framework "Foundation"
use scripting additions


-- isCusip :: String -> Bool
on isCusip(s)
    set cs to "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ*&#"
    set ns to mapMaybe(elemIndex(cs), s)
    
    script go
        on |λ|(f, x)
            set fx to apply(f, x)
            (fx div 10) + (fx mod 10)
        end |λ|
    end script
    
    9 = length of ns and item -1 of ns = (10 - (sum(zipWith(go, ¬
        cycle({my identity, my double}), ¬
        take(8, ns))) mod 10)) mod 10
end isCusip


-------------------------- TEST ---------------------------
on run
    script test
        on |λ|(s)
            s & " -> " & isCusip(s)
        end |λ|
    end script
    
    unlines(map(test, ¬
        {"037833100", "17275R102", "38259P508", ¬
            "594918104", "68389X106", "68389X105"}))
end run

-- 037833100 -> true
-- 17275R102 -> true
-- 38259P508 -> true
-- 594918104 -> true
-- 68389X106 -> false
-- 68389X105 -> true


-------------------- GENERIC FUNCTIONS --------------------

-- Just :: a -> Maybe a
on Just(x)
    -- Constructor for an inhabited Maybe (option type) value.
    -- Wrapper containing the result of a computation.
    {type:"Maybe", Nothing:false, Just:x}
end Just


-- Nothing :: Maybe a
on Nothing()
    -- Constructor for an empty Maybe (option type) value.
    -- Empty wrapper returned where a computation is not possible.
    {type:"Maybe", Nothing:true}
end Nothing


-- Tuple (,) :: a -> b -> (a, b)
on Tuple(a, b)
    -- Constructor for a pair of values, possibly of two different types.
    {type:"Tuple", |1|:a, |2|:b, length:2}
end Tuple


-- apply ($) :: (a -> b) -> a -> b
on apply(f, x)
    -- The value of f(x)
    mReturn(f)'s |λ|(x)
end apply


-- cycle :: [a] -> Generator [a]
on cycle(xs)
    script
        property lng : 1 + (length of xs)
        property i : missing value
        on |λ|()
            if missing value is i then
                set i to 1
            else
                set nxt to (1 + i) mod lng
                if 0 = ((1 + i) mod lng) then
                    set i to 1
                else
                    set i to nxt
                end if
            end if
            return item i of xs
        end |λ|
    end script
end cycle


-- double :: Num -> Num
on double(x)
    2 * x
end double


-- elemIndex :: Eq a => [a] -> a -> Maybe Int
on elemIndex(xs)
    script
        on |λ|(x)
            set lng to length of xs
            repeat with i from 1 to lng
                if x = (item i of xs) then return Just(i - 1)
            end repeat
            return Nothing()
        end |λ|
    end script
end elemIndex


-- identity :: a -> a
on identity(x)
    -- The argument unchanged.
    x
end identity


-- foldl :: (a -> b -> a) -> a -> [b] -> a
on foldl(f, startValue, xs)
    tell mReturn(f)
        set v to startValue
        set lng to length of xs
        repeat with i from 1 to lng
            set v to |λ|(v, item i of xs, i, xs)
        end repeat
        return v
    end tell
end foldl


-- length :: [a] -> Int
on |length|(xs)
    set c to class of xs
    if list is c or string is c then
        length of xs
    else
        (2 ^ 29 - 1) -- (maxInt - simple proxy for non-finite)
    end if
end |length|


-- map :: (a -> b) -> [a] -> [b]
on map(f, xs)
    -- The list obtained by applying f
    -- to each element of xs.
    tell mReturn(f)
        set lng to length of xs
        set lst to {}
        repeat with i from 1 to lng
            set end of lst to |λ|(item i of xs, i, xs)
        end repeat
        return lst
    end tell
end map


-- The mapMaybe function is a version of map which can throw out
-- elements. In particular, the functional argument returns
-- something of type Maybe b. If this is Nothing, no element is
-- added on to the result list. If it just Just b, then b is
-- included in the result list.
-- mapMaybe :: (a -> Maybe b) -> [a] -> [b]
on mapMaybe(mf, xs)
    script
        property g : mReturn(mf)
        on |λ|(a, x)
            set mb to g's |λ|(x)
            if Nothing of mb then
                a
            else
                a & (Just of mb)
            end if
        end |λ|
    end script
    foldl(result, {}, xs)
end mapMaybe


-- min :: Ord a => a -> a -> a
on min(x, y)
    if y < x then
        y
    else
        x
    end if
end min


-- mReturn :: First-class m => (a -> b) -> m (a -> b)
on mReturn(f)
    -- 2nd class handler function lifted into 1st class script wrapper. 
    if script is class of f then
        f
    else
        script
            property |λ| : f
        end script
    end if
end mReturn


-- sum :: [Num] -> Num
on sum(xs)
    script add
        on |λ|(a, b)
            a + b
        end |λ|
    end script
    
    foldl(add, 0, xs)
end sum


-- take :: Int -> [a] -> [a]
-- take :: Int -> String -> String
on take(n, xs)
    set c to class of xs
    if list is c then
        if 0 < n then
            items 1 thru min(n, length of xs) of xs
        else
            {}
        end if
    else if string is c then
        if 0 < n then
            text 1 thru min(n, length of xs) of xs
        else
            ""
        end if
    else if script is c then
        set ys to {}
        repeat with i from 1 to n
            set v to |λ|() of xs
            if missing value is v then
                return ys
            else
                set end of ys to v
            end if
        end repeat
        return ys
    else
        missing value
    end if
end take


-- unlines :: [String] -> String
on unlines(xs)
    -- A single string formed by the intercalation
    -- of a list of strings with the newline character.
    set {dlm, my text item delimiters} to ¬
        {my text item delimiters, linefeed}
    set str to xs as text
    set my text item delimiters to dlm
    str
end unlines


-- zipWith :: (a -> b -> c) -> [a] -> [b] -> [c]
on zipWith(f, xs, ys)
    set lng to min(|length|(xs), |length|(ys))
    if 1 > lng then return {}
    set xs_ to take(lng, xs) -- Allow for non-finite
    set ys_ to take(lng, ys) -- generators like cycle etc
    set lst to {}
    tell mReturn(f)
        repeat with i from 1 to lng
            set end of lst to |λ|(item i of xs_, item i of ys_)
        end repeat
        return lst
    end tell
end zipWith
Output:
037833100 -> true
17275R102 -> true
38259P508 -> true
594918104 -> true
68389X106 -> false
68389X105 -> true
Translation of: Ruby
validCUSIP?: function [cusip][
    s: 0
    alpha: 'A'..'Z'

    loop.with:'i chop cusip 'c [
        v: 0

        when.has: c [
            [|numeric?]     -> v: to :integer to :string c
            [|in? alpha]    -> v: (index alpha c) + 1 + 9
            [= '*']         -> v: 36
            [= '@']         -> v: 37
            [= '#']         -> v: 38
        ]

        if odd? i -> v: 2 * v

        s: s + (v / 10) + (v % 10)
    ]
    check: (10 - (s % 10)) % 10

    return check = to :integer to :string last cusip
]

loop ["037833100" "17275R102" "38259P508" "594918104" "68389X106" "68389X105"] 'cusip [
    print [cusip "=>" (validCUSIP? cusip)? -> "VALID" -> "INVALID"]
]
Output:
037833100 => VALID 
17275R102 => VALID 
38259P508 => VALID 
594918104 => VALID 
68389X106 => INVALID 
68389X105 => VALID
Cusip_Check_Digit(cusip){
    sum := 0, i := 1, x := StrSplit(cusip)
    while (i <= 8) {
        c := x[i]
        if c is digit
            v := c
        else if c is alpha
            v := Asc(c) - 64 + 9
        else if (c = "*")
            v := 36
        else if (c = "@")
            v := 37
        else if (c = "#")
            v := 38
        if (i/2 = Floor(i/2))
            v *= 2
        sum += Floor(v/10) + Mod(v, 10)
        i++
    }
    return (Mod(10 - Mod(sum, 10), 10) = x[9])
}

Examples:

data =
(
037833100
17275R102
38259P508
594918104
68389X106
68389X105
)

output := "Cusip`t`tValid`n"
loop, Parse, data, `n, `r
    output .= A_LoopField "`t" Cusip_Check_Digit(A_LoopField) "`n"
MsgBox % output
Output:
Cusip		Valid
037833100	1
17275R102	1
38259P508	1
594918104	1
68389X106	0
68389X105	1
# syntax: GAWK -f CUSIP.AWK
BEGIN {
    n = split("037833100,17275R102,38259P508,594918104,68389X106,68389X105",arr,",")
    for (i=1; i<=n; i++) {
      printf("%9s %s\n",arr[i],cusip(arr[i]))
    }
    exit(0)
}
function cusip(n,  c,i,sum,v,x) {
# returns: 1=OK, 0=NG, -1=bad data
    if (length(n) != 9) {
      return(-1)
    }
    for (i=1; i<=8; i++) {
      c = substr(n,i,1)
      if (c ~ /[0-9]/) {
        v = c
      }
      else if (c ~ /[A-Z]/) {
        v = index("ABCDEFGHIJKLMNOPQRSTUVWXYZ",c) + 9
      }
      else if (c == "*") {
        v = 36
      }
      else if (c == "@") {
        v = 37
      }
      else if (c == "#") {
        v = 38
      }
      else {
        return(-1)
      }
      if (i ~ /[02468]/) {
        v *= 2
      }
      sum += int(v / 10) + (v % 10)
    }
    x = (10 - (sum % 10)) % 10
    return(substr(n,9,1) == x ? 1 : 0)
}
Output:
037833100 1
17275R102 1
38259P508 1
594918104 1
68389X106 0
68389X105 1
Translation of: QuickBASIC
Works with: Decimal BASIC
100 REM CUSIP
110 DECLARE EXTERNAL SUB PrintVerdict
120 DECLARE EXTERNAL FUNCTION CusipCheckDigit
130 DECLARE EXTERNAL FUNCTION IsValidCusip
140 PRINT "CUSIP       Verdict"
150 CALL PrintVerdict("037833100")
160 CALL PrintVerdict("17275R102")
170 CALL PrintVerdict("38259P508")
180 CALL PrintVerdict("594918104")
190 CALL PrintVerdict("68389X106")
200 CALL PrintVerdict("68389X105")
210 END
220 REM **
230 EXTERNAL FUNCTION CusipCheckDigit(Cusip$)
240 LET I = 1
250 LET Sum = 0
260 LET L = LEN(Cusip$)
270 DO WHILE I < L
280    LET C$ = Cusip$(I:I)
290    IF ("0" <= C$) AND (C$ <= "9") THEN
300       LET V = VAL(C$)
310    ELSEIF ("A" <= C$) AND (C$ <= "Z") THEN
320       LET V = ORD(C$) - 65 + 10
330    ELSEIF C$ = "*" THEN
340       LET V = 36
350    ELSEIF C$ = "@" THEN
360       LET V = 37
370    ELSEIF C$ = "#" THEN
380       LET V = 38
390    ELSE
400       LET CusipCheckDigit = -1
410       EXIT FUNCTION
420    END IF
430    IF MOD(I - 1, 2) = 1 THEN LET V = 2 * V
440    IF I <= 8 THEN LET Sum = Sum + INT(V / 10) + MOD(V, 10)
450    LET I = I + 1
460 LOOP
470 IF I <> 9 THEN
480    LET CusipCheckDigit = -1
490 ELSE
500    LET CusipCheckDigit = MOD(10 - MOD(Sum, 10), 10)
510 END IF
520 END FUNCTION
530 REM **
540 EXTERNAL FUNCTION IsValidCusip (Cusip$)
550 LET Check = CusipCheckDigit(Cusip$)
560 IF Check < 0 THEN
570    LET IsValidCusip = 0
580 ELSEIF Cusip$(9:9) = CHR$(48 + Check) THEN
590    LET IsValidCusip = -1
600 ELSE
610    LET IsValidCusip = 0
620 END IF
630 END FUNCTION
640 REM **
650 EXTERNAL SUB PrintVerdict (Cusip$)
660 PRINT Cusip$;
670 IF IsValidCusip(Cusip$) <>0 THEN
680    PRINT " : Valid"
690 ELSE
700    PRINT " : Invalid"
710 END IF
720 END SUB
Output:
CUSIP       Verdict
037833100 : Valid
17275R102 : Valid
38259P508 : Valid
594918104 : Valid
68389X106 : Invalid
68389X105 : Valid
' version 04-04-2017
' compile with: fbc -s console

sub cusip(input_str As String)

    Print input_str;
    If Len(input_str) <> 9 Then
        Print " length is incorrect, invalid cusip"
        Return
    End If

    Dim As Long i, v , sum
    Dim As UByte x

    For i = 1 To 8
        x = input_str[i-1]
        Select Case x
            Case Asc("0") To Asc("9")
                v = x - Asc("0")
            Case Asc("A") To Asc("Z")
                v = x - Asc("A") + 1 + 9
            Case Asc("*")
                v= 36
            Case Asc("@")
                v = 37
            Case Asc("#")
                v = 38
            Case Else
                Print " found a invalid character, invalid cusip"
                return
        End Select

        If (i And 1) = 0 Then v = v * 2
        sum = sum + v \ 10 + v Mod 10
    Next

    sum = (10 - (sum Mod 10)) Mod 10
    If sum = (input_str[8] - Asc("0")) Then
        Print " is valid"
    Else
        Print " is invalid"
    End If

End Sub

' ------=< MAIN >=------

Data "037833100", "17275R102", "38259P508"
Data "594918104", "68389X106", "68389X105"

Dim As String input_str

Print
For i As Integer = 1 To 6
    Read input_str
    cusip(input_str)
Next

' empty keyboard buffer
While InKey <> "" : Wend
Print : Print "hit any key to end program"
Sleep
End
Output:
037833100 is valid
17275R102 is valid
38259P508 is valid
594918104 is valid
68389X106 is invalid
68389X105 is valid
Translation of: Modula-2
' CUSIP
DECLARE SUB PrintVerdict (Cusip$)
DECLARE FUNCTION CusipCheckDigit% (Cusip$)
DECLARE FUNCTION IsValidCusip% (Cusip$)
CONST TRUE% = -1, FALSE% = 0
PRINT "CUSIP       Verdict"
PrintVerdict "037833100"
PrintVerdict "17275R102"
PrintVerdict "38259P508"
PrintVerdict "594918104"
PrintVerdict "68389X106"
PrintVerdict "68389X105"
END

FUNCTION CusipCheckDigit% (Cusip$)
  I% = 1
  Sum% = 0
  L% = LEN(Cusip$)
  DO WHILE I% < L%
    IF ("0" <= MID$(Cusip$, I%, 1)) AND (MID$(Cusip$, I%, 1) <= "9") THEN
      V% = ASC(MID$(Cusip$, I%, 1)) - 48 ' 0
    ELSEIF ("A" <= MID$(Cusip$, I%, 1)) AND (MID$(Cusip$, I%, 1) <= "Z") THEN
      V% = ASC(MID$(Cusip$, I%, 1)) - 65 + 10
    ELSEIF MID$(Cusip$, I%, 1) = "*" THEN
      V% = 36
    ELSEIF MID$(Cusip$, I%, 1) = "@" THEN
      V% = 37
    ELSEIF MID$(Cusip$, I%, 1) = "#" THEN
      V% = 38
    ELSE
      CusipCheckDigit% = -1
      EXIT FUNCTION
    END IF
    IF (I% - 1) MOD 2 = 1 THEN V% = 2 * V%
    IF I% <= 8 THEN Sum% = Sum% + (V% \ 10) + (V% MOD 10)
    I% = I% + 1
  LOOP
  IF I% <> 9 THEN
    CusipCheckDigit% = -1
  ELSE
    CusipCheckDigit% = (10 - (Sum% MOD 10)) MOD 10
  END IF
END FUNCTION

FUNCTION IsValidCusip% (Cusip$)
  Check% = CusipCheckDigit%(Cusip$)
  IF Check% < 0 THEN
    IsValidCusip% = FALSE
  ELSE
    IsValidCusip% = (MID$(Cusip$, 9, 1) = CHR$(48 + Check%))
  END IF
END FUNCTION

SUB PrintVerdict (Cusip$)
  PRINT Cusip$;
  IF IsValidCusip%(Cusip$) THEN
    PRINT " : Valid"
  ELSE
    PRINT " : Invalid"
  END IF
END SUB
Output:
CUSIP       Verdict
037833100 : Valid
17275R102 : Valid
38259P508 : Valid
594918104 : Valid
68389X106 : Invalid
68389X105 : Valid
Private Function Cusip_Check_Digit(s As Variant) As Integer
    Dim Sum As Integer, c As String, v As Integer
    For i = 1 To 8
        c = Mid(s, i, 1)
        If IsNumeric(c) Then
            v = Val(c)
        Else
            Select Case c
                Case "a" To "z"
                    v = Asc(c) - Asc("a") + 10
                Case "A" To "Z"
                    v = Asc(c) - Asc("A") + 10
                Case "*"
                    v = 36
                Case "@"
                    v = 37
                Case "#"
                    v = 38
                Case Else
                    Debug.Print "not expected"
            End Select
        End If
        If i Mod 2 = 0 Then v = v * 2
        Sum = Sum + Int(v \ 10) + v Mod 10
    Next i
    Cusip_Check_Digit = (10 - (Sum Mod 10)) Mod 10
End Function
Output:
037833100     is valid
17275R102     is valid
38259P508     is valid
594918104     is valid
68389X106     not valid
68389X105     is valid
Translation of: C#
Module Module1

    Function IsCUSIP(s As String) As Boolean
        If s.Length <> 9 Then
            Return False
        End If

        Dim sum = 0
        For i = 0 To 7
            Dim c = s(i)

            Dim v As Integer
            If "0" <= c AndAlso c <= "9" Then
                v = Asc(c) - 48
            ElseIf "A" <= c AndAlso c <= "Z" Then
                v = Asc(c) - 55 ' Lower case letters are apparently invalid
            ElseIf c = "*" Then
                v = 36
            ElseIf c = "#" Then
                v = 38
            Else
                Return False
            End If

            If i Mod 2 = 1 Then
                v *= 2 ' check if odd as using 0-based indexing
            End If
            sum += v \ 10 + v Mod 10
        Next
        Return Asc(s(8)) - 48 = (10 - (sum Mod 10)) Mod 10
    End Function

    Sub Main()
        Dim candidates As New List(Of String) From {
            "037833100",
            "17275R102",
            "38259P508",
            "594918104",
            "68389X106",
            "68389X105"
        }

        For Each candidate In candidates
            Console.WriteLine("{0} -> {1}", candidate, If(IsCUSIP(candidate), "correct", "incorrect"))
        Next
    End Sub

End Module
Output:
037833100 -> correct
17275R102 -> correct
38259P508 -> correct
594918104 -> correct
68389X106 -> incorrect
68389X105 -> correct
Translation of: FreeBASIC
sub cusip(inputStr$)
    local i, v, sum, x$
 
    Print inputStr$;
    If Len(inputStr$) <> 9 Print " length is incorrect, invalid cusip" : return
 
    For i = 1 To 8
        x$ = mid$(inputStr$, i, 1)
        switch x$
            Case "*": v = 36 : break
            Case "@": v = 37 : break
            Case "#": v = 38 : break
            default:
                if x$ >= "A" and x$ <= "Z" then
                    v = asc(x$) - Asc("A") + 10
                elsif x$ >= "0" and x$ <= "9" then
                    v = asc(x$) - asc("0")
                else
                    Print " found a invalid character, invalid cusip"
                    return
                end if
        End switch
 
        If and(i, 1) = 0 v = v * 2
        sum = sum + int(v / 10) + mod(v, 10)
    Next
 
    sum = mod(10 - mod(sum, 10), 10)
    If sum = asc(mid$(inputStr$, 9, 1)) - Asc("0") Then
        Print " is valid"
    Else
        Print " is invalid"
    End If
 
End Sub
 
// ------=< MAIN >=------
 
Data "037833100", "17275R102", "38259P508"
Data "594918104", "68389X106", "68389X105", ""
 
Print
do
    Read inputStr$
    if inputStr$ = "" break
    cusip(inputStr$)
loop
get "libhdr"

let validcusip(c) = valof
$(  let sum = 0
    unless c%0 = 9 resultis false 
    for i = 1 to 8 do
    $(  let v = ( 2 - (i & 1) ) * valof
        $(  test '0' <= c%i <= '9'
                then resultis c%i - '0'
            or test 'A' <= c%i <= 'Z'
                then resultis 10 + c%i - 'A'
            or test c%i = '**'
                then resultis 36
            or test c%i = '@'
                then resultis 37
            or test c%i = '#'
                then resultis 38
            else resultis -1
        $)
        sum := sum + v/10 + v rem 10
    $)
    resultis (10 - (sum rem 10)) rem 10 = c%9 - '0'
$)

let show(c) be
    writef("%S: %Svalid*N", c, validcusip(c) -> "", "in")
    
let start() be
$(  show("037833100")
    show("17275R102")
    show("38259P508")
    show("594918104")
    show("68389X106")
    show("68389X105")
$)
Output:
037833100: valid
17275R102: valid
38259P508: valid
594918104: valid
68389X106: invalid
68389X105: valid
d  "0A*@#"+¨1026111
m  812
Check  ¯1(⊑=10|0-˜´10(|+⌊÷˜)m×↓)d⊐⊢

Check¨ "037833100""17275R102""38259P508""594918104""68389X106""68389X105"
Output:
⟨ 1 1 1 1 0 1 ⟩

C

Reads CUSIP strings from a file and prints results to console, usage printed on incorrect invocation.

#include<stdlib.h>
#include<stdio.h>

int cusipCheck(char str[10]){
	int sum=0,i,v;
	
	for(i=0;i<8;i++){
		if(str[i]>='0'&&str[i]<='9')
			v = str[i]-'0';
		else if(str[i]>='A'&&str[i]<='Z')
			v = (str[i] - 'A' + 10);
		else if(str[i]=='*')
			v = 36;
		else if(str[i]=='@')
			v = 37;
		else if(str[i]=='#')
			v = 38;
		if(i%2!=0)
			v*=2;
		
		sum += ((int)(v/10) + v%10);
	}
	return ((10 - (sum%10))%10);
}

int main(int argC,char* argV[])
{
	char cusipStr[10];
	
	int i,numLines;
	
	if(argC==1)
		printf("Usage : %s <full path of CUSIP Data file>",argV[0]);
	
	else{
		FILE* fp = fopen(argV[1],"r");
	
		fscanf(fp,"%d",&numLines);
		
		printf("CUSIP       Verdict\n");
		printf("-------------------");
		
		for(i=0;i<numLines;i++){
		
			fscanf(fp,"%s",cusipStr);
		
			printf("\n%s : %s",cusipStr,(cusipCheck(cusipStr)==(cusipStr[8]-'0'))?"Valid":"Invalid");
		}
	
		fclose(fp);
	}
	return 0;
}

Input file :

6
037833100
17275R102
38259P508
594918104
68389X106
68389X105

Invocation and output :

C:\rosettaCode>cusipCheck.exe cusipData.txt
CUSIP       Verdict
-------------------
037833100 : Valid
17275R102 : Valid
38259P508 : Valid
594918104 : Valid
68389X106 : Invalid
68389X105 : Valid
Translation of: Java
using System;
using System.Collections.Generic;

namespace CUSIP {
    class Program {
        static bool IsCusip(string s) {
            if (s.Length != 9) return false;
            int sum = 0;
            for (int i = 0; i <= 7; i++) {
                char c = s[i];

                int v;
                if (c >= '0' && c <= '9') {
                    v = c - 48;
                }
                else if (c >= 'A' && c <= 'Z') {
                    v = c - 55;  // lower case letters apparently invalid
                }
                else if (c == '*') {
                    v = 36;
                }
                else if (c == '#') {
                    v = 38;
                }
                else {
                    return false;
                }
                if (i % 2 == 1) v *= 2;  // check if odd as using 0-based indexing
                sum += v / 10 + v % 10;
            }
            return s[8] - 48 == (10 - (sum % 10)) % 10;
        }

        static void Main(string[] args) {
            List<string> candidates = new List<string>() {
                "037833100",
                "17275R102",
                "38259P508",
                "594918104",
                "68389X106",
                "68389X105"
            };
            foreach (var candidate in candidates) {
                Console.WriteLine("{0} -> {1}", candidate, IsCusip(candidate) ? "correct" : "incorrect");
            }
        }
    }
}
Output:
037833100 -> correct
17275R102 -> correct
38259P508 -> correct
594918104 -> correct
68389X106 -> incorrect
68389X105 -> correct
Translation of: C#
#include <iostream>
#include <vector>

bool isCusip(const std::string& s) {
    if (s.size() != 9) return false;

    int sum = 0;
    for (int i = 0; i <= 7; ++i) {
        char c = s[i];

        int v;
        if ('0' <= c && c <= '9') {
            v = c - '0';
        } else if ('A' <= c && c <= 'Z') {
            v = c - 'A' + 10;
        } else if (c = '*') {
            v = 36;
        } else if (c = '@') {
            v = 37;
        } else if (c = '#') {
            v = 38;
        } else {
            return false;
        }
        if (i % 2 == 1) {
            v *= 2;
        }
        sum += v / 10 + v % 10;
    }
    return s[8] - '0' == (10 - (sum % 10)) % 10;
}

int main() {
    using namespace std;

    vector<string> candidates{
        "037833100",
        "17275R102",
        "38259P508",
        "594918104",
        "68389X106",
        "68389X105"
    };

    for (auto str : candidates) {
        auto res = isCusip(str) ? "correct" : "incorrect";
        cout << str.c_str() << " -> " << res << "\n";
    }

    return 0;
}
Output:
037833100 -> correct
17275R102 -> correct
38259P508 -> correct
594918104 -> correct
68389X106 -> incorrect
68389X105 -> correct
Class Utils.Check [ Abstract ]
{

ClassMethod CUSIP(x As %String) As %Boolean
{
	SET x=$TRANSLATE(x," ")
	// https://leiq.bus.umich.edu/res_codes_cusip.htm
	IF x'?8UNP1N QUIT 0
	SET cd=$EXTRACT(x,*), x=$EXTRACT(x,1,*-1), t=0
	FOR i=1:1:$LENGTH(x) {
		SET n=$EXTRACT(x,i)
		IF n'=+n SET n=$CASE(n,"*":36,"@":37,"#":38,:$ASCII(n)-55)
		IF i#2=0 SET n=n*2
		SET t=t+(n\10)+(n#10)
	}
	QUIT cd=((10-(t#10))#10)
}

}
Examples:
USER>For  { Read s Quit:s=""  Write ": "_##class(Utils.Check).CUSIP(s), ! }         
037833100: 1
17275R102: 1
38259P508: 1
594918104: 1
68389X106: 0
68389X105: 1

USER>
(defn- char->value
  "convert the given char c to a value used to calculate the cusip check sum"
  [c]
  (let [int-char (int c)]
    (cond
      (and (>= int-char (int \0)) (<= int-char (int \9))) (- int-char 48)
      (and (>= int-char (int \A)) (<= int-char (int \Z))) (- int-char 55)
      (= c \*) 36
      (= c \@) 37
      (= c \#) 38
      :else nil)))

(defn- calc-sum
  "Calculate cusip sum. nil is returned for an invalid cusip."
  [cusip]
  (reduce
    (fn [sum [i c]]
      (if-let [v (char->value c)]
        (let [v (if (= (mod i 2) 1) (* v 2) v)]
          (+ sum (int (+ (/ v 10) (mod v 10)))))
        (reduced nil)))
    0
    (map-indexed vector (subs cusip 0 8))))

(defn calc-cusip-checksum
  "Given a valid 8 or 9 digit cusip, return the 9th checksum digit"
  [cusip]
  (when (>= (count cusip) 8)
    (let [sum (calc-sum cusip)]
      (when sum
        (mod (- 10 (mod sum 10)) 10)))))

(defn is-valid-cusip9?
  "predicate validating a 9 digit cusip."
  [cusip9]
  (when-let [checksum (and (= (count cusip9) 9)
                           (calc-cusip-checksum cusip9))]
    (= (- (int (nth cusip9 8)) 48)
       checksum)))

(defn rosetta-output
  "show some nice output for the Rosetta Wiki"
  []
  (doseq [cusip ["037833100" "17275R102" "38259P508" "594918104" "68389X106" "68389X105" "EXTRACRD8"
                 "EXTRACRD9" "BADCUSIP!" "683&9X106" "68389x105" "683$9X106" "68389}105" "87264ABE4"]]
    (println cusip (if (is-valid-cusip9? cusip) "valid" "invalid"))))
Output:
(rosetta-output)
037833100 valid
17275R102 valid
38259P508 valid
594918104 valid
68389X106 invalid
68389X105 valid
EXTRACRD8 invalid
EXTRACRD9 valid
BADCUSIP! invalid
683&9X106 invalid
68389x105 invalid
683$9X106 invalid
68389}105 invalid
87264ABE4 valid
valid_cusip = proc (s: string) returns (bool)
    own chars: string := "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ*@#"
    if string$size(s) ~= 9 then return(false) end
    sum: int := 0
    for i: int in int$from_to(1,8) do
        v: int := string$indexc(s[i], chars)-1
        if v<0 then return(false) end
        if i//2=0 then v := v*2 end
        sum := sum + v/10 + v//10
    end
    check: int := (10 - sum // 10) // 10
    return(check = string$indexc(s[9], chars)-1)
end valid_cusip

start_up = proc ()
    po: stream := stream$primary_output()
    cusips: array[string] := array[string]$[
        "037833100",
        "17275R102",
        "38259P508",
        "594918104",
        "68389X106",
        "68389X105"
    ]
    
    for cusip: string in array[string]$elements(cusips) do
        stream$puts(po, cusip || ": ")
        if valid_cusip(cusip)
            then stream$putl(po, "valid")
            else stream$putl(po, "invalid")
        end 
    end
end start_up
Output:
037833100: valid
17275R102: valid
38259P508: valid
594918104: valid
68389X106: invalid
68389X105: valid
(defun char->value (c)
  (cond ((digit-char-p c 36))
        ((char= c #\*) 36)
        ((char= c #\@) 37)
        ((char= c #\#) 38)
        (t (error "Invalid character: ~A" c))))

(defun cusip-p (cusip)
  (and (= 9 (length cusip))
       (loop for i from 1 to 8
             for c across cusip
             for v = (char->value c)
             when (evenp i)
               do (setf v (* 2 v))
             sum (multiple-value-bind (quot rem) (floor v 10)
                   (+ quot rem))
               into sum
             finally (return (eql (digit-char-p (char cusip 8))
                                  (mod (- 10 (mod sum 10)) 10))))))

(defun main ()
  (dolist (cusip '("037833100" "17275R102" "38259P508" "594918104" "68389X106" "68389X105"))
    (format t "~A: ~A~%" cusip (cusip-p cusip))))
Output:
037833100: T
17275R102: T
38259P508: T
594918104: T
68389X106: NIL
68389X105: T
def cusip_check (input)
  return false  unless input.size == 9
  sum = 0
  input.chars.each_with_index do |c, i|
    break if i == 8
    v = case c
        when .ascii_number?    then c.to_i
        when .ascii_uppercase? then c.ord - 'A'.ord + 10
        when '*'               then 36
        when '@'               then 37
        when '#'               then 38
        else return false
        end
    v *= 2 if (i+1).even?

    sum += v // 10 + v % 10
  end
  input[-1].to_i? == (10 - sum % 10) % 10
end

["037833100",
 "17275R102",
 "38259P508",
 "594918104",
 "68389X106",
 "68389X105"].each do |cusip|
  print cusip, ": ", cusip_check(cusip) ? "valid" : "invalid", "\n"
end
Output:
037833100: valid
17275R102: valid
38259P508: valid
594918104: valid
68389X106: invalid
68389X105: valid

D

import std.stdio;

void main(string[] args) {
    writeln("CUSIP       Verdict");
    foreach(arg; args[1..$]) {
        writefln("%9s : %s", arg, isValidCusip(arg) ? "Valid" : "Invalid");
    }
}

class IllegalCharacterException : Exception {
    this(string msg) {
        super(msg);
    }
}

bool isValidCusip(string cusip) in {
    assert(cusip.length == 9, "Incorrect cusip length");
} body {
    try {
        auto check = cusipCheckDigit(cusip);
        return cusip[8] == ('0' + check);
    } catch (IllegalCharacterException e) {
        return false;
    }
}

unittest {
    // Oracle Corporation
    assertEquals(isValidCusip("68389X105"), true);

    // Oracle Corporation (invalid)
    assertEquals(isValidCusip("68389X106"), false);
}

int cusipCheckDigit(string cusip) in {
    assert(cusip.length == 9, "Incorrect cusip length");
} body {
    int sum;
    for (int i=0; i<8; ++i) {
        char c = cusip[i];
        int v;

        switch(c) {
            case '0': .. case '9':
                v = c - '0';
                break;
            case 'A': .. case 'Z':
                v = c - 'A' + 10;
                break;
            case '*':
                v = 36;
                break;
            case '@':
                v = 37;
                break;
            case '#':
                v = 38;
                break;
            default:
                throw new IllegalCharacterException("Saw character: " ~ c);
        }
        if (i%2 == 1) {
            v = 2 * v;
        }

        sum = sum + (v / 10) + (v % 10);
    }

   return (10 - (sum % 10)) % 10;
}

unittest {
    // Apple Incorporated
    assertEquals(cusipCheckDigit("037833100"), 0);

    // Cisco Systems
    assertEquals(cusipCheckDigit("17275R102"), 2);

    // Google Incorporated
    assertEquals(cusipCheckDigit("38259P508"), 8);

    // Microsoft Corporation
    assertEquals(cusipCheckDigit("594918104"), 4);

    // Oracle Corporation
    assertEquals(cusipCheckDigit("68389X105"), 5);
}

version(unittest) {
    void assertEquals(T)(T actual, T expected) {
        import core.exception;
        import std.conv;
        if (actual != expected) {
            throw new AssertError("Actual [" ~ to!string(actual) ~ "]; Expected [" ~ to!string(expected) ~ "]");
        }
    }
}

/// Invoke with `cusip 037833100 17275R102 38259P508 594918104 68389X106 68389X105`
Output:
CUSIP       Verdict
037833100 : Valid
17275R102 : Valid
38259P508 : Valid
594918104 : Valid
68389X106 : Invalid
68389X105 : Valid
Works with: Delphi version 6.0

Using sets to simplify string parsing

type TCUSIPInfo = record
 ID,Company: string;
 end;

var CUSIPArray: array [0..5] of TCUSIPInfo = (
  (ID:'037833100'; Company: 'Apple Incorporated'),
  (ID:'17275R102'; Company: 'Cisco Systems'),
  (ID:'38259P508'; Company: 'Google Incorporated'),
  (ID:'594918104'; Company: 'Microsoft Corporation'),
  (ID:'68389X106'; Company: 'Oracle Corporation'),
  (ID:'68389X105'; Company: 'Oracle Corporation'));

function IsValidCUSIP(Info: TCUSIPInfo): boolean;
{Calculate checksum on first 7 chars of CUSIP }
{And compare with the last char - the checksum char}
var I,V,Sum: integer;
var C: char;
begin
Sum:=0;
for I:=1 to Length(Info.ID)-1 do
	begin
	C:=Info.ID[I];
	if C in ['0'..'9'] then V:=byte(C)-$30
	else if C in ['A'..'Z'] then V:=(byte(C)-$40) + 9
	else case C of
	 '*': V:=36;
	 '@': V:=37;
	 '#': V:=38;
	 end;
	if (I and 1)=0 then V:=V*2;
	Sum:=Sum + (V div 10) + (V mod 10);
	end;
Sum:=(10 - (Sum mod 10)) mod 10;
Result:=StrToInt(Info.ID[Length(Info.ID)])=Sum;
end;


procedure TestCUSIPList(Memo: TMemo);
{Test every item in the CSUIP array}
var I: integer;
var S: string;
begin
for I:=0 to High(CUSIPArray) do
	begin
	if IsValidCUSIP(CUSIPArray[I]) then S:='Valid' else S:='Invalid';
	Memo.Lines.Add(CUSIPArray[I].ID+'	'+CUSIPArray[I].Company+':	'+S);
	end;
end;
Output:
037833100	Apple Incorporated:	Valid
17275R102	Cisco Systems:		Valid
38259P508	Google Incorporated:	Valid
594918104	Microsoft Corporation:	Valid
68389X106	Oracle Corporation:	Invalid
68389X105	Oracle Corporation:	Valid


Translation of: Go
func isCusip(s) {
    if s.Length() != 9 { return false }
    var sum = 0
    for i in 0..7 {
        var c = s[i]
        var v =
            match c {
                '0'..'9' => c.Order() - 48,
                'A'..'Z' => c.Order() - 55,
                '*' => 36,
                '@' => 37,
                '#' => 38,
                _ => false
            }
        if i % 2 == 1 { v *= 2 }
        sum += v / 10 + v % 10
    }
    s[8].Order() - 48 == (10 - (sum % 10)) % 10
}
 
var candidates = [
    "037833100",
    "17275R102",
    "38259P508",
    "594918104",
    "68389X106",
    "68389X105"
]
 
for candidate in candidates {
    var b =
        if isCusip(candidate) {
            "correct"
        } else {
            "incorrect"
        }
    print("\(candidate) -> \(b)")
}
Output:
037833100 -> correct
17275R102 -> correct
38259P508 -> correct
594918104 -> correct
68389X106 -> incorrect
68389X105 -> correct
func check inp$ .
   for i = 1 to 8
      c = strcode substr inp$ i 1
      if c >= 48 and c <= 57
         v = c - 48
      elif c >= 65 and c <= 91
         v = c - 64 + 9
      elif c = 42
         v = 36
      elif c = 64
         v = 37
      elif c = 35
         v = 38
      .
      if i mod 2 = 0 : v *= 2
      sum += v div 10 + v mod 10
   .
   return if (10 - sum mod 10) mod 10 = number substr inp$ 9 1
.
for s$ in [ "037833100" "17275R102" "38259P508" "594918104" "68389X106" "68389X105" ]
   write s$ & " is "
   if check s$ = 1
      print "valid"
   else
      print "invalid"
   .
.
Output:
037833100 is valid
17275R102 is valid
38259P508 is valid
594918104 is valid
68389X106 is invalid
68389X105 is valid

LAMBDA

Binding the names ISCUSIP and CUSIPMAP to the following lambda expressions in the Name Manager of the Excel WorkBook:

(See LAMBDA: The ultimate Excel worksheet function)

=LAMBDA(s,
    LET(
        ns, VLOOKUP(
            CHARS(s), CUSIPMAP, 2, FALSE
        ),
        
        AND(
            9 = COLUMNS(ns),
            LET(
                firstEight, INITCOLS(ns),
                
                ixs, SEQUENCE(1, 8),
                
                evensDoubled, IF(ISEVEN(ixs),
                    2 * INDEX(firstEight, 1, ixs),
                    INDEX(firstEight, 1, ixs)
                ),
                
                LASTCOL(ns) = MOD(
                    10 - MOD(
                        SUM(
                            QUOTIENT(evensDoubled, 10),
                            MOD(evensDoubled, 10)
                        ), 
                        10
                    ), 
                    10
                )
            )
        )
    )
)


CUSIPMAP
={"0",0;"1",1;"2",2;"3",3;"4",4;"5",5;"6",6;"7",7;"8",8;"9",9;"A",
10;"B",11;"C",12;"D",13;"E",14;"F",15;"G",16;"H",17;"I",18;"J",19;"K",
20;"L",21;"M",22;"N",23;"O",24;"P",25;"Q",26;"R",27;"S",28;"T",29;"U",
30;"V",31;"W",32;"X",33;"Y",34;"Z",35;"*",36;"@",37;"#",38}

and also assuming the following generic bindings in the Name Manager for the WorkBook:

CHARS
=LAMBDA(s,
    MID(
        s,
        SEQUENCE(1, LEN(s), 1, 1),
        1
    )
)


INITCOLS
=LAMBDA(xs,
    INDEX(
        xs,
        SEQUENCE(
            1,
            COLUMNS(xs) - 1,
            1,
        )
    )
)


LASTCOL
=LAMBDA(xs,
    INDEX(
        xs,
        SEQUENCE(ROWS(xs), 1, 1, 1),
        COLUMNS(xs)
    )
)
Output:
fx =ISCUSIP(A2)
A B
1 Strings CUSIP verdicts
2 037833100 TRUE
3 17275R102 TRUE
4 38259P508 TRUE
5 594918104 TRUE
6 68389X106 FALSE
7 68389X105 TRUE
// Validate CUSIP: Nigel Galloway. June 2nd., 2021
let fN=function n when n>47 && n<58->n-48 |n when n>64 && n<91->n-55 |42->36 |64->37 |_->38
let cD(n:string)=(10-(fst((n.[0..7])|>Seq.fold(fun(z,n)g->let g=(fN(int g))*(n+1) in (z+g/10+g%10,(n+1)%2))(0,0)))%10)%10=int(n.[8])-48
["037833100";"17275R102";"38259P508";"594918104";"68389X103";"68389X105"]|>List.iter(fun n->printfn "CUSIP %s is %s" n (if cD n then "valid" else "invalid"))
Output:
CUSIP 037833100 is valid
CUSIP 17275R102 is valid
CUSIP 38259P508 is valid
CUSIP 594918104 is valid
CUSIP 68389X103 is invalid
CUSIP 68389X105 is valid
Real: 00:00:00.009
USING: combinators.short-circuit formatting kernel math
math.parser qw regexp sequences unicode ;
IN: rosetta-code.cusip

: cusip-check-digit ( seq -- n )
    but-last-slice [
        [ dup alpha? [ digit> ] [ "*@#" index 36 + ] if ] dip
        odd? [ 2 * ] when 10 /mod +
    ] map-index sum 10 mod 10 swap - 10 mod ;

: cusip? ( seq -- ? )
    {
        [ R/ [0-9A-Z*@#]+/ matches? ]
        [ [ last digit> ] [ cusip-check-digit ] bi = ]
    } 1&& ;

qw{ 037833100 17275R102 38259P508 594918104 68389X106 68389X105 }
[ dup cusip? "correct" "incorrect" ? "%s -> %s\n" printf ] each
Output:
037833100 -> correct
17275R102 -> correct
38259P508 -> correct
594918104 -> correct
68389X106 -> incorrect
68389X105 -> correct

The key notion here is to employ a single sequence of valid characters, VALID, and for each character C of the code under test, use function INDEX(VALID,C) to find its position within that sequence, which turns out to be the desired v of the example pseudocode. The only slight difficulty is that INDEX starts its counting with one for the first character of VALID, which is zero, so one must be subtracted; similarly, to return a digit character code via indexing into VALID, one must be added. By using a list of valid characters rather than peculiar character arithmetic (such as c <= "9" & c >= "0" or similar) there is no reliance on the ASCII way of things. Recall that EBCDIC encodements have different orderings and notably, non-alphabetic characters between A and Z.

The source does not bother with the MODULE protocol of F90 and later, and so the type of function CUSIPCHECK must be declared in all routines wishing to invoke it. However, the F90 feature of having the END statement of a subroutine or function give its name is to valuable to ignore. The function returns a character code rather than an integer, since the presumption is that it is to be compared to the check character of the code being inspected, which is known as a character not an integer. This means some blather when extracting the eight characters to be presented to CUSIPCHECK and comparing the result to the ninth character, but the test can be done in one expression.

There is no checking that only valid characters are presented, nor that eight-character codes only are offered, though the compiler might complain if the function were to be invoked with a text literal of the wrong size. In the absence of such checks, there need be no added complications to support a scheme for reporting such errors.

      CHARACTER*1 FUNCTION CUSIPCHECK(TEXT)	!Determines the check sum character.
Committee on Uniform Security Identification Purposes, of the American (i.e. USA) Bankers' Association.
       CHARACTER*8 TEXT		!Specifically, an eight-symbol code.
       CHARACTER*(*) VALID	!These only are valid.
       PARAMETER (VALID = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ*@#")
       INTEGER I,V,S		!Assistants.
        S = 0		!Start the checksum.
        DO I = 1,LEN(TEXT)	!Step through the text.
          V = INDEX(VALID,TEXT(I:I)) - 1	!Since counting starts with one.
          IF (MOD(I,2).EQ.0) V = V*2		!V = V*(2 - MOD(I,2))?
          S = S + V/10 + MOD(V,10)		!Specified calculation.
        END DO			!On to the next character.
        I = MOD(10 - MOD(S,10),10) + 1	!Again, counting starts with one.
        CUSIPCHECK = VALID(I:I)	!Thanks to the MOD 10, surely a digit.
      END FUNCTION CUSIPCHECK	!No checking for invalid input...

      PROGRAM POKE	!Just to try it out.
      INTEGER I,N	!Assistants.
      PARAMETER (N = 6)		!A whole lot of blather
      CHARACTER*9 CUSIP(N)	!Just to have an array of test codes.
      DATA CUSIP/		!Here they are, as specified.
     1  "037833100",
     2  "17275R102",
     3  "38259P508",
     4  "594918104",
     5  "68389X106",
     6  "68389X105"/
      CHARACTER*1 CUSIPCHECK	!Needed as no use of the MODULE protocol.

      DO I = 1,N	!"More than two? Use a DO..."
        WRITE (6,*) CUSIP(I),CUSIPCHECK(CUSIP(I)(1:8)).EQ.CUSIP(I)(9:9)
      END DO

      END

Output: standard output is to I/O unit 6, and free-format (the *) will suffice for this. Each line output starts with a space (in case it is to go to a lineprinter, with carriage control), which is convenient for layout here.

037833100 T
17275R102 T
38259P508 T
594918104 T
68389X106 F
68389X105 T

This would have worked first time, except that a fymgre frmble caused the omission of the digit 2 from the text of VALID. The benefits of checking checksums reach to unexpected places!


include "NSLog.incl"

local fn VerifyCUSIP( cusipStr as CFStringRef ) as CFStringRef
  NSUInteger   i, v, sum = 0, count = len(cusipStr)
  CFStringRef  resultStr
  
  if count != 9 then exit fn = @"Invalid length"
  
  for i = 0 to 7
    unichar x = fn StringCharacterAtIndex( cusipStr, i )
    select x
      case _"*" : v = 36
      case _"@" : v = 37
      case _"#" : v = 38
      case else
        if ( x >= _"0" and x <= _"9" )
          v = x - _"0"
        else
          if ( x >= _"A" and x <= _"Z" )
            v = x - _"A" + 10
          else
            exit fn = fn StringWithFormat( @"Invalid character: %c", x )
          end if
        end if
    end select
    
    if ( i and 1 ) then v = v * 2
    
    sum += (v / 10) + (v mod 10)
  next
  sum = ((10-(sum mod 10)) mod 10)
  
  if (sum == ( fn StringCharacterAtIndex( cusipStr, 8 ) - _"0" ))
    resultStr = @"Valid"
  else
    resultStr = @"Invalid"
  end If
end fn = resultStr

NSLog( @"0378331009: %@", fn VerifyCUSIP( @"0378331009" ) ) // Invalid length expected
NSLog( @"037833100:  %@", fn VerifyCUSIP( @"037833100"  ) ) // Valid expected
NSLog( @"17275R102:  %@", fn VerifyCUSIP( @"17275R102"  ) ) // Valid expected
NSLog( @"38259P508:  %@", fn VerifyCUSIP( @"38259P508"  ) ) // Valid expected
NSLog( @"594918104:  %@", fn VerifyCUSIP( @"594918104"  ) ) // Valid expected
NSLog( @"68389X106:  %@", fn VerifyCUSIP( @"68389X106"  ) ) // Invalid expected
NSLog( @"68389X105:  %@", fn VerifyCUSIP( @"68389X105"  ) ) // Valid expected
NSLog( @"683&9X105:  %@", fn VerifyCUSIP( @"683&9X105"  ) ) // Invalid character expected: &

HandleEvents
Output:
0378331009: Invalid length
037833100:  Valid
17275R102:  Valid
38259P508:  Valid
594918104:  Valid
68389X106:  Invalid
68389X105:  Valid
683&9X105:  Invalid character: &
package main

import "fmt"

func isCusip(s string) bool {
    if len(s) != 9 { return false }
    sum := 0
    for i := 0; i < 8; i++ {
        c := s[i]
        var v int
        switch {
            case c >= '0' && c <= '9':
                v = int(c) - 48
            case c >= 'A' && c <= 'Z':
                v = int(c) - 55
            case c == '*':
                v = 36
            case c == '@':
                v = 37
            case c == '#':
                v = 38
            default:
                return false
        }
        if i % 2 == 1 { v *= 2 }  // check if odd as using 0-based indexing
        sum += v/10 + v%10
    }
    return int(s[8]) - 48 == (10 - (sum%10)) % 10
}

func main() {
    candidates := []string {
        "037833100",
        "17275R102",
        "38259P508",
        "594918104",
        "68389X106",
        "68389X105",
    }

    for _, candidate := range candidates {
        var b string
        if isCusip(candidate) {
            b = "correct"
        } else {
            b = "incorrect"
        }
        fmt.Printf("%s -> %s\n", candidate, b)
    }
}
Output:
037833100 -> correct
17275R102 -> correct
38259P508 -> correct
594918104 -> correct
68389X106 -> incorrect
68389X105 -> correct
Translation of: Java
class Cusip {
    private static Boolean isCusip(String s) {
        if (s.length() != 9) return false
        int sum = 0
        for (int i = 0; i <= 7; i++) {
            char c = s.charAt(i)

            int v
            if (c >= ('0' as char) && c <= ('9' as char)) {
                v = c - 48
            } else if (c >= ('A' as char) && c <= ('Z' as char)) {
                v = c - 55  // lower case letters apparently invalid
            } else if (c == '*' as char) {
                v = 36
            } else if (c == '@' as char) {
                v = 37
            } else if (c == '#' as char) {
                v = 38
            } else {
                return false
            }
            if (i % 2 == 1) v *= 2  // check if odd as using 0-based indexing
            sum += v / 10 + v % 10
        }
        return s.charAt(8) - 48 == (10 - (sum % 10)) % 10
    }

    static void main(String[] args) {
        List<String> candidates=new ArrayList<>()
        candidates.add("037833100")
        candidates.add("17275R102")
        candidates.add("38259P508")
        candidates.add("594918104")
        candidates.add("68389X106")
        candidates.add("68389X105")
        for (String candidate : candidates) {
            System.out.printf("%s -> %s%n", candidate, isCusip(candidate) ? "correct" : "incorrect")
        }
    }
}
Output:
037833100 -> correct
17275R102 -> correct
38259P508 -> correct
594918104 -> correct
68389X106 -> incorrect
68389X105 -> correct
import Data.List(elemIndex)

data Result = Valid | BadCheck | TooLong | TooShort | InvalidContent deriving Show

-- convert a list of Maybe to a Maybe list.
-- result is Nothing if any of values from the original list are Nothing
allMaybe :: [Maybe a] -> Maybe [a]
allMaybe = sequence

toValue :: Char -> Maybe Int
toValue c = elemIndex c $ ['0'..'9'] ++ ['A'..'Z'] ++ "*@#" 

-- check a list of ints to see if they represent a valid CUSIP
valid :: [Int] -> Bool
valid ns0 = 
    let -- multiply values with even index by 2
        ns1 = zipWith (\i n -> (if odd i then n else 2*n)) [1..] $ take 8 ns0

        -- apply div/mod formula from site and sum up results
        sm = sum $ fmap (\s -> ( s `div` 10 ) + s `mod` 10) ns1

    in  -- apply mod/mod formula from site and compare to last value in list
        ns0!!8 == (10 - (sm `mod` 10)) `mod` 10

-- check a String to see if it represents a valid CUSIP
checkCUSIP :: String -> Result
checkCUSIP cs 
       | l < 9     = TooShort
       | l > 9     = TooLong
       | otherwise = case allMaybe (fmap toValue cs) of
                         Nothing -> InvalidContent
                         Just ns -> if valid ns then Valid else BadCheck
    where l = length cs

testData =  
    [ "037833100"
    , "17275R102"
    , "38259P508"
    , "594918104"
    , "68389X106"
    , "68389X105"
    ]

main = mapM_ putStrLn (fmap (\s -> s ++ ": " ++ show (checkCUSIP s)) testData)
Output:
037833100: Valid
17275R102: Valid
38259P508: Valid
594918104: Valid
68389X106: BadCheck
68389X105: Valid

Or, picking some other possibilities from Haskell's rich libraries:

import qualified Data.Map as M (Map, fromList, lookup)
import Data.Maybe (fromMaybe)

-------------------------- CUSIP -------------------------

cusipMap :: M.Map Char Int
cusipMap =
  M.fromList $
    zip (['0' .. '9'] <> ['A' .. 'Z'] <> "*@#") [0 ..]

cusipValid :: String -> Bool
cusipValid s =
  let ns = (fromMaybe [] . traverse (`M.lookup` cusipMap)) s
   in (9 == length ns)
        && let qrSum =
                 sum $
                   ( [quot, rem]
                       <*> zipWith
                         id
                         (cycle [id, (* 2)])
                         (take 8 ns)
                   )
                     <*> [10]
            in last ns == rem (10 - rem qrSum 10) 10

--------------------------- TEST -------------------------
main :: IO ()
main =
  mapM_
    (print . ((,) <*> cusipValid))
    [ "037833100",
      "17275R102",
      "38259P508",
      "594918104",
      "68389X106",
      "68389X105"
    ]
Output:
("037833100",True)
("17275R102",True)
("38259P508",True)
("594918104",True)
("68389X106",False)
("68389X105",True)
# cusip.icn -- Committee on Uniform Security Identification Procedures

procedure main()
   local code, codes
   codes := ["037833100", "17275R102", "38259P508",
            "594918104", "68389X106", "68389X105"]
   while code := pop(codes) do {
      writes(code, " : ")
      if check_code(code) then
         write("valid.")
      else write("not valid.")
      }
end

procedure check_code(c)
   local p, sum, value
   static codetable
   initial codetable := buildtable()

   sum   := 0
   value := 0
   every p := 1 to 8 do {
      if p % 2 = 1 then    # odd position
         value := codetable[c[p]] 
      else                 # even position
         value := 2 * codetable[c[p]]
      sum +:= (value / 10) + (value % 10)
      }
   sum := (10 - (sum % 10)) % 10
   if sum = c[9] then return else fail
end

procedure buildtable()
   local chars, n, t
   t := table()
   chars := &digits || &ucase || "*@#"
   every n := 1 to *chars do
      t[chars[n]] := (n - 1)
   return t
end
Output:
037833100 : valid.

17275R102 : valid. 38259P508 : valid. 594918104 : valid. 68389X106 : not valid. 68389X105 : valid.

J

One-liner:

   ccd =. 10 | 10 - 10 | [: +/ [: , 10 (#.^:_1) (8 $ 1 2) * '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ*@#' i. ]
   ccd '68389X10'
5

More verbose version that checks for correct input:

   CUSIPcheckdigit =. 3 : 0
assert. 8 = $ y NB. Only accept an 8-element long list
assert. */ y e. '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ*@#' NB. Only accept characters from the list of 38
values =. (8 $ 1 2) * '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ*@#' i. ] NB. Verb to translate characters and then double every second value.
sumdigits =. +/@,@(10 10&#:) NB. Verb to sum the base-10 digits in a numerical array
invertedmod =. 10 | 10 - 10 | ] NB. Verb to find the mod-10 of 10 minus mod-10
": invertedmod sumdigits values y NB. Return the check digit as a character
)
   addCUSIPcheckdigit =: , CUSIPcheckdigit
   verifyCUSIPcheckdigit =: {: = CUSIPcheckdigit@}:

Examples:

   addCUSIPcheckdigit '68389X10'
68389X105
   verifyCUSIPcheckdigit '68389X106'
0
   verifyCUSIPcheckdigit '68389X105'
1
   samples =: '037833100', '17275R102', '38259P508', '594918104', '68389X106',: '68389X105'
   samples ; verifyCUSIPcheckdigit"1 samples
┌─────────┬─┐
0378331001
17275R1021
38259P5081
5949181041
68389X1060
68389X1051
└─────────┴─┘
Translation of: Kotlin

Uses Java 9

import java.util.List;

public class Cusip {
    private static Boolean isCusip(String s) {
        if (s.length() != 9) return false;
        int sum = 0;
        for (int i = 0; i <= 7; i++) {
            char c = s.charAt(i);

            int v;
            if (c >= '0' && c <= '9') {
                v = c - 48;
            } else if (c >= 'A' && c <= 'Z') {
                v = c - 55;  // lower case letters apparently invalid
            } else if (c == '*') {
                v = 36;
            } else if (c == '@') {
                v = 37;
            } else if (c == '#') {
                v = 38;
            } else {
                return false;
            }
            if (i % 2 == 1) v *= 2;  // check if odd as using 0-based indexing
            sum += v / 10 + v % 10;
        }
        return s.charAt(8) - 48 == (10 - (sum % 10)) % 10;
    }

    public static void main(String[] args) {
        List<String> candidates = List.of(
                "037833100", "17275R102", "38259P508", "594918104", "68389X106", "68389X105", "EXTRACRD8",
                "EXTRACRD9", "BADCUSIP!", "683&9X106", "68389x105", "683$9X106", "68389}105", "87264ABE4"
        );
        for (String candidate : candidates) {
            System.out.printf("%s -> %s%n", candidate, isCusip(candidate) ? "correct" : "incorrect");
        }
    }
}
Output:
037833100 -> correct
17275R102 -> correct
38259P508 -> correct
594918104 -> correct
68389X106 -> incorrect
68389X105 -> correct
EXTRACRD8 -> incorrect
EXTRACRD9 -> correct
BADCUSIP! -> incorrect
683&9X106 -> incorrect
68389x105 -> incorrect
683$9X106 -> incorrect
68389}105 -> incorrect
87264ABE4 -> correct
(() => {
    'use strict';

    // cusipValid = Dict Char Int -> String -> Bool
    const cusipValid = charMap => s => {
        const
            ns = fromMaybe([])(
                traverse(flip(lookupDict)(charMap))(
                    chars(s)
                )
            );
        return 9 === ns.length && (
            last(ns) === rem(
                10 - rem(
                    sum(apList(
                        apList([quot, rem])(
                            zipWith(identity)(
                                cycle([identity, x => 2 * x])
                            )(take(8)(ns))
                        )
                    )([10]))
                )(10)
            )(10)
        );
    };

    //----------------------- TEST ------------------------
    // main :: IO ()
    const main = () => {

        // cusipMap :: Dict Char Int
        const cusipMap = dictFromList(
            zip(chars(
                "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ*@#"
            ))(enumFrom(0)));

        console.log(unlines(map(
            apFn(
                s => validity => s + ' -> ' + str(validity)
            )(cusipValid(cusipMap))
        )([
            '037833100',
            '17275R102',
            '38259P508',
            '594918104',
            '68389X106',
            '68389X105'
        ])));
    };


    //----------------- GENERIC FUNCTIONS -----------------

    // Just :: a -> Maybe a
    const Just = x => ({
        type: 'Maybe',
        Nothing: false,
        Just: x
    });


    // Nothing :: Maybe a
    const Nothing = () => ({
        type: 'Maybe',
        Nothing: true,
    });


    // Tuple (,) :: a -> b -> (a, b)
    const Tuple = a =>
        b => ({
            type: 'Tuple',
            '0': a,
            '1': b,
            length: 2
        });


    // apFn :: (a -> b -> c) -> (a -> b) -> a -> c
    const apFn = f =>
        // Applicative instance for functions.
        // f(x) applied to g(x).
        g => x => f(x)(
            g(x)
        );


    // apList (<*>) :: [(a -> b)] -> [a] -> [b]
    const apList = fs =>
        // The sequential application of each of a list
        // of functions to each of a list of values.
        xs => fs.flatMap(
            f => xs.map(f)
        );


    // append (++) :: [a] -> [a] -> [a]
    // append (++) :: String -> String -> String
    const append = xs =>
        // A list or string composed by
        // the concatenation of two others.
        ys => xs.concat(ys);


    // chars :: String -> [Char]
    const chars = s =>
        s.split('');


    // cons :: a -> [a] -> [a]
    const cons = x =>
        xs => Array.isArray(xs) ? (
            [x].concat(xs)
        ) : 'GeneratorFunction' !== xs
        .constructor.constructor.name ? (
            x + xs
        ) : ( // cons(x)(Generator)
            function*() {
                yield x;
                let nxt = xs.next()
                while (!nxt.done) {
                    yield nxt.value;
                    nxt = xs.next();
                }
            }
        )();


    // cycle :: [a] -> Generator [a]
    function* cycle(xs) {
        const lng = xs.length;
        let i = 0;
        while (true) {
            yield(xs[i])
            i = (1 + i) % lng;
        }
    }


    // dictFromList :: [(k, v)] -> Dict
    const dictFromList = kvs =>
        Object.fromEntries(kvs);


    // enumFrom :: Enum a => a -> [a]
    function* enumFrom(x) {
        // A non-finite succession of enumerable
        // values, starting with the value x.
        let v = x;
        while (true) {
            yield v;
            v = succ(v);
        }
    }


    // flip :: (a -> b -> c) -> b -> a -> c
    const flip = f =>
        1 < f.length ? (
            (a, b) => f(b, a)
        ) : (x => y => f(y)(x));


    // fromEnum :: Enum a => a -> Int
    const fromEnum = x =>
        typeof x !== 'string' ? (
            x.constructor === Object ? (
                x.value
            ) : parseInt(Number(x))
        ) : x.codePointAt(0);


    // fromMaybe :: a -> Maybe a -> a
    const fromMaybe = def =>
        // A default value if mb is Nothing
        // or the contents of mb.
        mb => mb.Nothing ? def : mb.Just;


    // fst :: (a, b) -> a
    const fst = tpl =>
        // First member of a pair.
        tpl[0];


    // identity :: a -> a
    const identity = x =>
        // The identity function. (`id`, in Haskell)
        x;


    // last :: [a] -> a
    const last = xs =>
        // The last item of a list.
        0 < xs.length ? xs.slice(-1)[0] : undefined;


    // length :: [a] -> Int
    const length = xs =>
        // Returns Infinity over objects without finite
        // length. This enables zip and zipWith to choose
        // the shorter argument when one is non-finite,
        // like cycle, repeat etc
        (Array.isArray(xs) || 'string' === typeof xs) ? (
            xs.length
        ) : Infinity;


    // liftA2 :: (a -> b -> c) -> Maybe a -> Maybe b -> Maybe c
    const liftA2 = f => a => b =>
        a.Nothing ? a : b.Nothing ? b : Just(f(a.Just)(b.Just));


    // lookupDict :: a -> Dict -> Maybe b
    const lookupDict = k => dct => {
        const v = dct[k];
        return undefined !== v ? (
            Just(v)
        ) : Nothing();
    };

    // map :: (a -> b) -> [a] -> [b]
    const map = f =>
        // The list obtained by applying f
        // to each element of xs.
        // (The image of xs under f).
        xs => (
            Array.isArray(xs) ? (
                xs
            ) : xs.split('')
        ).map(f);


    // pureMay :: a -> Maybe a
    const pureMay = x => Just(x);

    // Given a type name string, returns a
    // specialised 'pure', where
    // 'pure' lifts a value into a particular functor.

    // pureT :: String -> f a -> (a -> f a)
    const pureT = t => x =>
        'List' !== t ? (
            'Either' === t ? (
                pureLR(x)
            ) : 'Maybe' === t ? (
                pureMay(x)
            ) : 'Node' === t ? (
                pureTree(x)
            ) : 'Tuple' === t ? (
                pureTuple(x)
            ) : pureList(x)
        ) : pureList(x);


    // pureTuple :: a -> (a, a)
    const pureTuple = x =>
        Tuple('')(x);

    // quot :: Int -> Int -> Int
    const quot = n =>
        m => Math.floor(n / m);

    // rem :: Int -> Int -> Int
    const rem = n => m => n % m;

    // snd :: (a, b) -> b
    const snd = tpl => tpl[1];

    // str :: a -> String
    const str = x =>
        x.toString();

    // succ :: Enum a => a -> a
    const succ = x => {
        const t = typeof x;
        return 'number' !== t ? (() => {
            const [i, mx] = [x, maxBound(x)].map(fromEnum);
            return i < mx ? (
                toEnum(x)(1 + i)
            ) : Error('succ :: enum out of range.')
        })() : x < Number.MAX_SAFE_INTEGER ? (
            1 + x
        ) : Error('succ :: Num out of range.')
    };

    // sum :: [Num] -> Num
    const sum = xs =>
        // The numeric sum of all values in xs.
        xs.reduce((a, x) => a + x, 0);

    // take :: Int -> [a] -> [a]
    // take :: Int -> String -> String
    const take = n =>
        // The first n elements of a list,
        // string of characters, or stream.
        xs => 'GeneratorFunction' !== xs
        .constructor.constructor.name ? (
            xs.slice(0, n)
        ) : [].concat.apply([], Array.from({
            length: n
        }, () => {
            const x = xs.next();
            return x.done ? [] : [x.value];
        }));

    // The first argument is a sample of the type
    // allowing the function to make the right mapping

    // toEnum :: a -> Int -> a
    const toEnum = e => x =>
        ({
            'number': Number,
            'string': String.fromCodePoint,
            'boolean': Boolean,
            'object': v => e.min + v
        } [typeof e])(x);


    // traverse :: (Applicative f) => (a -> f b) -> [a] -> f [b]
    const traverse = f =>
        // Collected results of mapping each element
        // of a structure to an action, and evaluating
        // these actions from left to right.
        xs => 0 < xs.length ? (() => {
            const
                vLast = f(xs.slice(-1)[0]),
                t = vLast.type || 'List';
            return xs.slice(0, -1).reduceRight(
                (ys, x) => liftA2(cons)(f(x))(ys),
                liftA2(cons)(vLast)(pureT(t)([]))
            );
        })() : [
            []
        ];


    // uncons :: [a] -> Maybe (a, [a])
    const uncons = xs => {
        // Just a tuple of the head of xs and its tail,
        // Or Nothing if xs is an empty list.
        const lng = length(xs);
        return (0 < lng) ? (
            Infinity > lng ? (
                Just(Tuple(xs[0])(xs.slice(1))) // Finite list
            ) : (() => {
                const nxt = take(1)(xs);
                return 0 < nxt.length ? (
                    Just(Tuple(nxt[0])(xs))
                ) : Nothing();
            })() // Lazy generator
        ) : Nothing();
    };


    // uncurry :: (a -> b -> c) -> ((a, b) -> c)
    const uncurry = f =>
        // A function over a pair, derived
        // from a curried function.
        x => ((...args) => {
            const
                xy = 1 < args.length ? (
                    args
                ) : args[0];
            return f(xy[0])(xy[1]);
        })(x);


    // unlines :: [String] -> String
    const unlines = xs =>
        // A single string formed by the intercalation
        // of a list of strings with the newline character.
        xs.join('\n');


    // zip :: [a] -> [b] -> [(a, b)]
    const zip = xs =>
        // Use of `take` and `length` here allows for zipping with non-finite
        // lists - i.e. generators like cycle, repeat, iterate.
        ys => {
            const
                lng = Math.min(length(xs), length(ys)),
                vs = take(lng)(ys);
            return take(lng)(xs).map(
                (x, i) => Tuple(x)(vs[i])
            );
        };

    // Use of `take` and `length` here allows zipping with non-finite lists
    // i.e. generators like cycle, repeat, iterate.

    // zipWith :: (a -> b -> c) -> [a] -> [b] -> [c]
    const zipWith = f => xs => ys => {
        const lng = Math.min(length(xs), length(ys));
        return Infinity > lng ? (() => {
            const
                as = take(lng)(xs),
                bs = take(lng)(ys);
            return Array.from({
                length: lng
            }, (_, i) => f(as[i])(
                bs[i]
            ));
        })() : zipWithGen(f)(xs)(ys);
    };


    // zipWithGen :: (a -> b -> c) ->
    // Gen [a] -> Gen [b] -> Gen [c]
    const zipWithGen = f => ga => gb => {
        function* go(ma, mb) {
            let
                a = ma,
                b = mb;
            while (!a.Nothing && !b.Nothing) {
                let
                    ta = a.Just,
                    tb = b.Just
                yield(f(fst(ta))(fst(tb)));
                a = uncons(snd(ta));
                b = uncons(snd(tb));
            }
        }
        return go(uncons(ga), uncons(gb));
    };

    // MAIN ---
    return main();
})();
Output:
037833100 -> true
17275R102 -> true
38259P508 -> true
594918104 -> true
68389X106 -> false
68389X105 -> true

Adapted from Wren

Works with: jq

Also works with gojq, the Go implementation of jq, and with jackson-jq and fq.

def isCusip:
  length == 9 and
  explode as $s
  | {sum: 0, i: 0}
  | until(. == false or .i == 8;
      $s[.i] as $c
      | (if ($c >= 48 and $c <= 57)    # '0' to '9'
         then $c - 48
         elif ($c >= 65 and $c <= 90)  # 'A' to 'Z'
         then $c - 55
         elif $c == 42                 # '*'
         then 36
         elif $c == 64                 # '@'
         then 37
         elif $c == 35                 # '#'
         then 38
         else false                    # return false
         end ) as $v
      | if $v == false then false
        else # check if odd as using 0-based indexing
            (if (.i%2 == 1) then 2 * $v else $v end) as $v
        | .sum += (($v/10)|floor) + $v%10 
        | .i += 1
        end )
  | if . == false then false
    else $s[8] - 48 == (10 - (.sum%10)) % 10
    end;

def candidates: [
    "037833100",
    "17275R102",
    "38259P508",
    "594918104",
    "68389X106",
    "68389X105"
];

candidates[]
| "\(.) -> \(if isCusip then "correct" else "incorrect" end)"
Output:
037833100 -> correct
17275R102 -> correct
38259P508 -> correct
594918104 -> correct
68389X106 -> incorrect
68389X105 -> correct
Works with: Julia version 0.6
module CUSIP

function _lastdigitcusip(input::AbstractString)
    input = uppercase(input)
    s = 0

    for (i, c) in enumerate(input)
        if isdigit(c)
            v = Int(c) - 48
        elseif isalpha(c)
            v = Int(c) - 64 + 9
        elseif c == '*'
            v = 36
        elseif c == '@'
            v = 37
        elseif c == '#'
            v = 38
        end

        if iseven(i); v *= 2 end
        s += div(v, 10) + rem(v, 10)
    end

    return Char(rem(10 - rem(s, 10), 10) + 48)
end

checkdigit(input::AbstractString) = input[9] == _lastdigitcusip(input[1:8])

end  # module CUSIP

for code in ("037833100", "17275R102", "38259P508", "594918104", "68389X106", "68389X105")
    println("$code is ", CUSIP.checkdigit(code) ? "correct." : "not correct.")
end
Output:
037833100 is correct.
17275R102 is correct.
38259P508 is correct.
594918104 is correct.
68389X106 is not correct.
68389X105 is correct.
// version 1.1.0

fun isCusip(s: String): Boolean {
    if (s.length != 9) return false
    var sum = 0
    for (i in 0..7) {
        val c = s[i]
        var v = when (c) {
            in '0'..'9'  -> c.toInt() - 48
            in 'A'..'Z'  -> c.toInt() - 55  // lower case letters apparently invalid
            '*'          -> 36
            '@'          -> 37
            '#'          -> 38
            else         -> return false
        }
        if (i % 2 == 1) v *= 2  // check if odd as using 0-based indexing
        sum += v / 10 + v % 10
    }
    return s[8].toInt() - 48  == (10 - (sum % 10)) % 10
}

fun main(args: Array<String>) {
    val candidates = listOf(
        "037833100",
        "17275R102",
        "38259P508",
        "594918104",
        "68389X106",
        "68389X105"
    )
    for (candidate in candidates) 
        println("$candidate -> ${if(isCusip(candidate)) "correct" else "incorrect"}")
}
Output:
037833100 -> correct
17275R102 -> correct
38259P508 -> correct
594918104 -> correct
68389X106 -> incorrect
68389X105 -> correct

If we don't strictly follow the pseudo-code, we can do this.

val isCusip = fn(s string) {
    if len(s) != 9 : return false

    val basechars = '0'..'9' & 'A'..'Z' & "*@#"

    val sum = for[=0] i of 8 {
        var v = index(basechars, by=s2s(s, of=i))
        if not v: return false
        v = v[1]-1
        if i div 2: v *= 2
        _for += v \ 10 + v rem 10
    }

    s[9]-'0' == (10-(sum rem 10)) rem 10
}

val candidates = fw/037833100 17275R102 38259P508 594918104 68389X106 68389X105/

for c in candidates {
    writeln c, ": ", if(isCusip(c): "good" ; "bad")
}

Following the pseudo-code would look more like the following.

Translation of: Go
val isCusip = fn(s string) {
    if len(s) != 9 : return false

    val basechars = '0'..'9' & 'A'..'Z' & "*@#"

    val sum = for[=0] i of 8 {
        val c = s[i]
        var v = 0

        switch[and] c {
            case in '0'..'9':
                v = c-'0'

            case in 'A'..'Z':
                v = c-55 # c-'A'+10

            case '*': v = 36
            case '@': v = 37
            case '#': v = 38

            default: return false
        }

        if i div 2: v *= 2
        _for += v \ 10 + v rem 10
    }

    s[9]-'0' == (10-(sum rem 10)) rem 10
}

val candidates = fw/037833100 17275R102 38259P508 594918104 68389X106 68389X105/

for c in candidates {
    writeln c, ": ", if(isCusip(c): "good" ; "bad")
}
Output:
037833100: good
17275R102: good
38259P508: good
594918104: good
68389X106: bad
68389X105: good
Translation of: Pascal-P
(* CUSIP *)

block

  unit check_digit: function (cusip: string): integer;
  var
    sum, v, i_first, i_last, i: integer,
    c: character,
    check_needed: boolean,
    ccusip: arrayof character;
  begin
    sum := 0;
    ccusip := unpack(cusip);
    i, i_first := lower(ccusip);
    i_last := upper(ccusip);
    check_needed := true;
    while (i < i_last) and check_needed
    do  
      c := ccusip(i);
      if ord(c) >= ord('0') and ord(c) <= ord('9')
      then
        v := ord(c) - ord('0') 
      else 
        if ord('A') <= ord(c) and ord(c) <= ord('Z')
        then
          v := ord(c) - ord('A') + 10
        else 
          case c
            when '*': v := 36;
            when '@': v := 37;
            when '#': v := 38;
            otherwise
              result := -1;
              check_needed := false
          esac
        fi
      fi;
      if check_needed
      then
        if (i - i_first) mod 2 = 1 then v := 2 * v fi;
        if i - i_first <= 7 then sum := sum + v div 10 + v mod 10 fi;
        i := i + 1
      fi;
    od;
    if check_needed
    then  
      if i - i_first =/= 8
      then
        result := -1
      else
        result := (10 - sum mod 10) mod 10
      fi;
    fi;  
  end check_digit;

  unit is_valid: function (cusip: string): boolean;
  var
    check: integer,
    ccusip: arrayof character;  
  begin
    check := check_digit(cusip);
    if check < 0
    then
      result := false
    else
      ccusip := unpack(cusip);
      result := ord(ccusip(lower(ccusip) + 8)) = ord('0') + check
    fi;
  end is_valid;

  unit write_verdict: procedure (cusip: string);
  begin
    if is_valid(cusip)
    then
      writeln(cusip, " : Valid")
    else
      writeln(cusip, " : Invalid")
    fi
  end write_verdict;

begin
  writeln("CUSIP       Verdict");
  call write_verdict("037833100");
  call write_verdict("17275R102");  
  call write_verdict("38259P508");
  call write_verdict("594918104");
  call write_verdict("68389X106");
  call write_verdict("68389X105");
end;
Output:
CUSIP       Verdict
037833100 : Valid
17275R102 : Valid
38259P508 : Valid
594918104 : Valid
68389X106 : Invalid
68389X105 : Valid

The checkDigit function is a line-for-line translation of the pseudo-code algorithm.

function checkDigit (cusip)
  if #cusip ~= 8 then return false end
  
  local sum, c, v, p = 0
  for i = 1, 8 do
    c = cusip:sub(i, i)
    if c:match("%d") then
      v = tonumber(c)
    elseif c:match("%a") then
      p = string.byte(c) - 55
      v = p + 9
    elseif c == "*" then
      v = 36
    elseif c == "@" then
      v = 37
    elseif c == "#" then
      v = 38
    end
    if i % 2 == 0 then
      v = v * 2
    end
    
    sum = sum + math.floor(v / 10) + v % 10
  end
  
  return tostring((10 - (sum % 10)) % 10)
end

local testCases = {
  "037833100",
  "17275R102",
  "38259P508",
  "594918104",
  "68389X106",
  "68389X105"
}
for _, CUSIP in pairs(testCases) do
  io.write(CUSIP .. ": ")
  if checkDigit(CUSIP:sub(1, 8)) == CUSIP:sub(9, 9) then
    print("VALID")
  else
    print("INVALID")
  end
end
Output:
037833100: VALID
17275R102: VALID
38259P508: VALID
594918104: VALID
68389X106: INVALID
68389X105: VALID
ClearAll[Cusip]
rules = Thread[(ToString /@ Range[0, 9]) -> Range[0, 9]]~Join~
   Thread[CharacterRange["A", "Z"] -> Range[26] + 9]~Join~
   Thread[Characters["*@#"] -> {36, 37, 38}];
Cusip[cusip_String] := Module[{s = cusip, sum = 0, c, value, check},
  If[StringLength[s] != 9,
   Print["Cusip must be 9 characters!"];
   False
   ,
   s = Characters[ToUpperCase[s]];
   Do[
    c = s[[i]];
    value = c /. rules;
    If[EvenQ[i], value *= 2];
    sum += Floor[value/10] + Mod[value, 10];
    ,
    {i, 8}
    ];
   check = Mod[(10 - Mod[sum, 10]), 10];
   s[[-1]] === ToString[check]
   ]
  ]
Cusip /@ {"037833100", "17275R102", "38259P508", "594918104", "68389X106", "68389X105"}
Output:
{True, True, True, True, False, True}
isCusip = function(s)
  if s.len != 9 then return false
  sum = 0
  for i in range(0, 7)
    c = s[i]
    v = 0
    if c >= "0" and c <= "9" then
      v = code(c) - 48
    else if c >= "A" and c <= "Z" then
      v = code(c) - 55
    else if c == "*" then
      v = 36
    else if c == "@" then
      v = 37
    else if c == "#" then
      v = 38
    else
      return false
    end if
    if i%2 == 1 then v *= 2 // check if odd as using 0-based indexing
    sum += floor(v/10) + v%10
  end for
  return code(s[8]) - 48 == (10 - (sum%10)) % 10
end function

candidates = [
  "037833100", "17275R102", "38259P508",
  "594918104", "68389X106", "68389X105",
]
for candidate in candidates
  s = "valid"
  if not isCusip(candidate) then s = "invalid"
  print candidate + " -> " + s
end for
Output:
037833100 -> valid
17275R102 -> valid
38259P508 -> valid
594918104 -> valid
68389X106 -> invalid
68389X105 -> valid
MODULE CUSIP;
FROM FormatString IMPORT FormatString;
FROM Terminal IMPORT WriteString,WriteLn,ReadChar;

PROCEDURE WriteInt(n : INTEGER);
VAR buf : ARRAY[0..10] OF CHAR;
BEGIN
    FormatString("%i", buf, n);
    WriteString(buf)
END WriteInt;

PROCEDURE cusipCheckDigit(cusip : ARRAY OF CHAR) : INTEGER;
VAR
    i,v,sum : INTEGER;
BEGIN
    i := 0;
    sum := 0;
    WHILE cusip[i] # 0C DO
        IF ('0' <= cusip[i]) AND (cusip[i] <= '9') THEN
            v := ORD(cusip[i]) - 48 (* 0 *)
        ELSIF ('A' <= cusip[i]) AND (cusip[i] <= 'Z') THEN
            v := ORD(cusip[i]) - 65 (* A *) + 10
        ELSIF cusip[i] = '*' THEN
            v := 36
        ELSIF cusip[i] = '@' THEN
            v := 37
        ELSIF cusip[i] = '#' THEN
            v := 38
        ELSE
            RETURN -1
        END;
        IF i MOD 2 = 1 THEN v := 2 * v END;
        IF i < 8 THEN
            sum := sum + (v DIV 10) + (v MOD 10);
        END;
        INC(i)
    END;

    IF i # 9 THEN RETURN -1 END;
    RETURN (10 - (sum MOD 10)) MOD 10
END cusipCheckDigit;

PROCEDURE isValidCusip(cusip : ARRAY OF CHAR) : BOOLEAN;
VAR
    check : INTEGER;
BEGIN
    check := cusipCheckDigit(cusip);
    IF check < 0 THEN RETURN FALSE END;
    RETURN cusip[8] = CHR(48 (* 0 *) + check)
END isValidCusip;

PROCEDURE Print(cusip : ARRAY OF CHAR);
BEGIN
    WriteString(cusip);
    IF isValidCusip(cusip) THEN
        WriteString(" : Valid")
    ELSE
        WriteString(" : Invalid")
    END;
    WriteLn
END Print;

(* main *)
BEGIN
    WriteString("CUSIP       Verdict");
    WriteLn;

    Print("037833100");
    Print("17275R102");
    Print("38259P508");
    Print("594918104");
    Print("68389X106");
    Print("68389X105");

    ReadChar
END CUSIP.
Output:
CUSIP       Verdict
037833100 : Valid
17275R102 : Valid
38259P508 : Valid
594918104 : Valid
68389X106 : Invalid
68389X105 : Valid
def cusip_checksum(cusip)
    alpha = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    num   = "0123456789"
    sum   = 0

    for i in range(1, 8)
        c = cusip[i - 1]
        v = 0
        if c in num
            v = int(c)
        else if c in alpha
            p = alpha[c] + 1
            v = p + 9
        else if c in "*@#"
            v = "*@#"[c] + 36
        end
        if (i % 2) = 0
            v *= 2
        end

        sum += int(v / 10) + (v % 10)
    end

    return (10 - (sum % 10)) % 10
end

if main
    codes = {"037833100", "17275R102", "38259P508",\
             "594918104", "68389X106", "68389X105"}

    for code in codes
        if int(code[len(code) - 1]) = cusip_checksum(code)
            println code + " is valid"
        else
            println code + " is invalid"
        end
    end
end
Output:
037833100 is valid
17275R102 is valid
38259P508 is valid
594918104 is valid
68389X106 is invalid
68389X105 is valid
import strutils

proc cusipCheck(cusip: string): bool =
  if cusip.len != 9:
    return false
  
  var 
    sum, v = 0
  for i, c in cusip[0 .. ^2]:
    if c.isDigit:
      v = parseInt($c)
    elif c.isUpperAscii:
      v = ord(c) - ord('A') + 10
    elif c == '*':
      v = 36
    elif c == '@':
      v = 37
    elif c == '#':
      v = 38
    
    if i mod 2 == 1:
      v *= 2
    
    sum += v div 10 + v mod 10
  let check = (10 - (sum mod 10)) mod 10
  return $check == $cusip[^1]

proc main =
  let codes = [
    "037833100",
    "17275R102",
    "38259P508",
    "594918104",
    "68389X106",
    "68389X105"
  ]

  for code in codes:
    echo code, ": ", if cusipCheck(code): "Valid" else: "Invalid"

main()
Output:
037833100: Valid
17275R102: Valid
38259P508: Valid
594918104: Valid
68389X106: Invalid
68389X105: Valid
Translation of: ALGOL 68
MODULE Cusip; (* validate CUSIP codes *)
    IMPORT   Strings, Out;

    CONST    cusipBase      = 39;
             cusipLength    = 9;
    VAR      cusipDigits    : ARRAY cusipBase + 1 OF CHAR; (* 39 digits + trailing nul *)

    (* returns TRUE if cusip is a valid CUSIP code, FALSE otherwise *)
    PROCEDURE isCusip( cusip : ARRAY OF CHAR ) : BOOLEAN;
        VAR    sum, digit, cPos, checkDigit    : INTEGER;
               isValid                         : BOOLEAN;

        (* returns the base 39 digit corresponding to a character of a CUSIP code *)
        PROCEDURE cusipDigit( cChar : CHAR ) : INTEGER;
            VAR   digit, dPos       : INTEGER;
            BEGIN
                digit := -999;
                dPos  := 0;
                WHILE ( dPos <= cusipBase ) & ( digit < 0 ) DO
                    IF cusipDigits[ dPos ] = cChar THEN digit := dPos END;
                    INC( dPos )
                END
            RETURN digit
            END cusipDigit ;

        BEGIN
            IF Strings.Length( cusip ) # cusipLength THEN
                isValid := FALSE       (* invalid length code *)
            ELSE
                (* CUSIP code has the correct length *)
                sum        := 0;
                checkDigit := cusipDigit( cusip[ cusipLength - 1 ] );
                FOR cPos   := 0 TO cusipLength - 2 DO
                    digit  := cusipDigit( cusip[ cPos ] );
                    IF ODD( cPos ) THEN digit := digit * 2 END;
                    INC( sum, ( digit DIV 10 ) + ( digit MOD 10 ) )
                END;
                isValid := ( 10 - ( sum MOD 10 ) ) MOD 10 = checkDigit
            END
        RETURN isValid
        END isCusip ;

    PROCEDURE testCusip( cusip : ARRAY OF CHAR ) ;
        BEGIN
            Out.String( cusip );
            IF isCusip( cusip ) THEN Out.String( " valid" ) ELSE Out.String( " invalid" ) END;
            Out.Ln
        END testCusip;

BEGIN

    cusipDigits := "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ*@#";

    testCusip( "037833100" );
    testCusip( "17275R102" );
    testCusip( "38259P508" );
    testCusip( "594918104" );
    testCusip( "68389X106" );
    testCusip( "68389X105" )
END Cusip.
Output:
037833100 valid
17275R102 valid
38259P508 valid
594918104 valid
68389X106 invalid
68389X105 valid
Translation of: Kotlin
class Cusip {
    function : native : IsCusip(s : String) ~ Bool {
        if(s->Size() <> 9) {
            return false;
        };

        sum := 0;
        for(i := 0; i < 7; i+=1;) {
            c := s->Get(i);
 
            v : Int;
            if (c >= '0' & c <= '9') {
                v := c - 48;
            } else if (c >= 'A' & c <= 'Z') {
                v := c - 55;  # lower case letters apparently invalid
            } else if (c = '*') {
                v := 36;
            } else if (c = '@') {
                v := 37;
            } else if (c = '#') {
                v := 38;
            } else {
                return false;
            };
        
            # check if odd as using 0-based indexing
            if(i % 2 = 1) {
                v *= 2;
            }; 

            sum += v / 10 + v % 10;
        };

        return s->Get(8) - 48 = (10 - (sum % 10)) % 10;
    }
 
    function : Main(args : String[]) ~ Nil {
        candidates := [
            "037833100",
            "17275R102",
            "38259P508",
            "594918104",
            "68389X106",
            "68389X105"
        ];

        each(i : candidates) {
            candidate := candidates[i];
            "{$candidate} => "->Print(); 
            if(IsCusip(candidate)) {
                "correct"->PrintLine();
            }
            else {
                "incorrect"->PrintLine();
            };
        };
    }
}

Output:

037833100 => correct
17275R102 => correct
38259P508 => correct
594918104 => correct
68389X106 => incorrect
68389X105 => correct
Translation of: Modula-2

Because Pascal-P does not have exit from function, an additional flag is introduced. The flag tells if checking should be continued. Also, the array of char is indexed from 1 like strings in Pascal.

Works with: Pascal-P version P4
program cusip(output);

const
  cusiplen = 9;

type
  tcusip = array [1 .. cusiplen] of char;

  function cusipcheckdigit(cusip: tcusip): integer;
    (* Check digit *)
  var
    i, sum, v: integer;
    c: char;
    contcheck: boolean; (* Continue checking? *)
  begin
    i := 1;
    sum := 0;
    contcheck := true;
    while (i <= cusiplen) and contcheck do
    begin
      c := cusip[i];
      if ('0' <= c) and (c <= '9') then v := ord(c) - 48
      else if ('A' <= c) and (c <= 'Z') then v := ord(c) - 65 + 10
      else if c = '*' then v := 36
      else if c = '@' then v := 37
      else if c = '#' then v := 38
      else
      begin
        cusipcheckdigit := -1;
        contcheck := false;
      end;
      if contcheck then
      begin
        if (i - 1) mod 2 = 1 then v := 2 * v;
        if i <= 8 then sum := sum + (v div 10) + (v mod 10);
        i := i + 1;
      end;
    end;
    if contcheck then
      if i <> 10 then cusipcheckdigit := -1
      else cusipcheckdigit := (10 - (sum mod 10)) mod 10;
  end;

  function isvalidcusip(cusip: tcusip): boolean;
  var
    check: integer;
  begin
    check := cusipcheckdigit(cusip);
    if check < 0 then isvalidcusip := false
    else isvalidcusip := (ord(cusip[9]) = ord(48 + check));
  end;

  procedure writeverdict(cusip: tcusip);
  (* Write the verdict *)
  begin
    write(cusip);
    if isvalidcusip(cusip) then writeln(' : Valid')
    else writeln(' : Invalid');
  end;

begin
  writeln('CUSIP       Verdict');
  writeverdict('037833100');
  writeverdict('17275R102');
  writeverdict('38259P508');
  writeverdict('594918104');
  writeverdict('68389X106');
  writeverdict('68389X105');
  (* readln; *)
end.
Output:
CUSIP       Verdict
037833100 : Valid
17275R102 : Valid
38259P508 : Valid
594918104 : Valid
68389X106 : Invalid
68389X105 : Valid
function IsCusip(s: string): boolean;
begin
  result := false;
  if (s.Length <> 9) then exit;
  var sum := 0;
  var v := 0;
  for var i := 1 to 8 do
  begin
    var c := s[i];
    if c.isdigit then 
      v := c.todigit
    else if (c >= 'A') and (c <= 'Z') then 
      v := ord(c) - ord('A') + 10  
    else if c = '*' then 
      v := 36
    else if c = '@' then 
      v := 37
    else if c = '#' then 
      v := 38;
    if (i mod 2) = 0 then 
      v := v * 2;
    sum += (v div 10) + (v mod 10);
  end;
  var check := (10 - (sum mod 10)) mod 10;
  result := s[9].todigit = check;
end;

begin
  var candidates := |'037833100', '17275R102', '38259P508', '594918104', '68389X106', '68389X105'|;
  foreach var candidate in candidates do
    println(candidate, if IsCusip(candidate) then 'correct' else 'incorrect');
end.
Output:
037833100 correct
17275R102 correct
38259P508 correct
594918104 correct
68389X106 incorrect
68389X105 correct
$cv{$_} = $i++ for '0'..'9', 'A'..'Z', '*', '@', '#';

sub cusip_check_digit {
    my @cusip = split m{}xms, shift;
    my $sum = 0;

    for $i (0..7) {
        return 'Invalid character found' unless $cusip[$i] =~ m{\A [[:digit:][:upper:]*@#] \z}xms;
        $v  = $cv{ $cusip[$i] };
        $v *= 2 if $i%2;
        $sum += int($v/10) + $v%10;
    }

    $check_digit = (10 - ($sum%10)) % 10;
    $check_digit == $cusip[8] ? '' : ' (incorrect)';
}

my %test_data = (
    '037833100' => 'Apple Incorporated',
    '17275R102' => 'Cisco Systems',
    '38259P508' => 'Google Incorporated',
    '594918104' => 'Microsoft Corporation',
    '68389X106' => 'Oracle Corporation',
    '68389X105' => 'Oracle Corporation',
);

print "$_ $test_data{$_}" . cusip_check_digit($_) . "\n" for sort keys %test_data;
Output:
037833100 Apple Incorporated
17275R102 Cisco Systems
38259P508 Google Incorporated
594918104 Microsoft Corporation
68389X105 Oracle Corporation
68389X106 Oracle Corporation (incorrect)
with javascript_semantics

sequence cch = {}

function CusipCheckDigit(string cusip)
    if length(cch)=0 then
        cch = repeat(-1,256)
        cch['0'..'9'] = tagset(9,0)
        cch['A'..'Z'] = tagset(35,10)
        cch['*'] = 36
        cch['@'] = 37
        cch['#'] = 38
    end if
    if length(cusip)!=9 or find('\0',cusip) then return 0 end if
    integer s = 0
    for i,c in cusip to 8 do
        integer v = cch[c]
        if v=-1 then return 0 end if
        if even(i) then v *= 2 end if
        s += floor(v/10)+mod(v,10)
    end for
    return cusip[9]==mod(10-mod(s,10),10)+'0'
end function
 
sequence tests = {"037833100",  -- Apple Incorporated
                  "17275R102",  -- Cisco Systems
                  "38259P508",  -- Google Incorporated
                  "594918104",  -- Microsoft Corporation
                  "68389X106",  -- Oracle Corporation   (incorrect)
                  "68389X105"}  -- Oracle Corporation
for ti in tests do
    printf(1,"%s : %svalid\n",{ti,iff(CusipCheckDigit(ti)?"":"in")})
end for
Output:
037833100 : valid
17275R102 : valid
38259P508 : valid
594918104 : valid
68389X106 : invalid
68389X105 : valid
function IsCusip(string $s) {
    if (strlen($s) != 9) return false;
    $sum = 0;
    for ($i = 0; $i <= 7; $i++) {
        $c = $s[$i];
        if (ctype_digit($c)) {
            // if character is numeric, get character's numeric value
            $v = intval($c);
        } elseif (ctype_alpha($c)) {
            // if character is alphabetic, get character's ordinal position in alphabet
            $position = ord(strtoupper($c)) - ord('A') + 1;
            $v = $position + 9;
        } elseif ($c == "*") {
            $v = 36;
        } elseif ($c == "@") {
            $v = 37;
        } elseif ($c == "#") {
            $v = 38;
        } else {
            return false;
        }
        // is this character position even?
        if ($i % 2 == 1) {
            $v *= 2;
        }
        // calculate the checksum digit
        $sum += floor($v / 10 ) + ( $v % 10 );
    }
    return ord($s[8]) - 48 == (10 - ($sum % 10)) % 10;
}

$cusips = array("037833100",
                "17275R102",
                "38259P508",
                "594918104",
                "68389X106",
                "68389X105");

foreach ($cusips as $cusip) echo $cusip . " -> " . (IsCusip($cusip) ? "valid" : "invalid") . "\n";
Output:
037833100 -> valid
17275R102 -> valid
38259P508 -> valid
594918104 -> valid
68389X106 -> invalid
68389X105 -> valid
(de cusip (Str)
   (let (Str (mapcar char (chop Str))  S 0)
      (for (I . C) (head 8 Str)
         (let V
            (cond
               ((<= 48 C 57) (- C 48))
               ((<= 65 C 90) (+ 10 (- C 65)))
               ((= C 42) 36)
               ((= C 64) 37)
               ((= C 35) 38) )
            (or
               (bit? 1 I)
               (setq V (>> -1 V)) )
            (inc
               'S
               (+ (/ V 10) (% V 10)) ) ) )
      (=
         (- (last Str) 48)
         (% (- 10 (% S 10)) 10) ) ) )

(println
   (mapcar
      cusip
      (quote
         "037833100"
         "17275R102"
         "38259P508"
         "68389X106"
         "68389X105" ) ) )
Output:
(T T T NIL T)
Translation of: Wren
local function is_cusip(s)
    if #s != 9 then return false end
    local sum = 0
    for i = 1, 8 do
        local c = s[i]
        local v = switch true do
            case c >= '0' and c <= '9' -> c:byte() - 48
            case c >= 'A' and c <= 'Z' -> c:byte() - 55
            case c == "*" -> 36
            case c == "@" -> 37
            case c == "#" -> 38
            default        -> nil
        end
        if !v then return false end
        if i % 2 == 0 then v = v * 2 end  -- check if even as using 1-based indexing
        sum += v // 10 + v % 10
    end
    return s[9]:byte() - 48 == (10 - (sum % 10)) % 10
end

local candidates = {
    "037833100",
    "17275R102",
    "38259P508",
    "594918104",
    "68389X106",
    "68389X105"
}

for candidates as candidate do
    local b = is_cusip(candidate) ? "correct" : "incorrect"
    print($"{candidate} -> {b}")
end
Output:
037833100 -> correct
17275R102 -> correct
38259P508 -> correct
594918104 -> correct
68389X106 -> incorrect
68389X105 -> correct
function Get-CheckDigitCUSIP {
    [CmdletBinding()]
    [OutputType([int])]
    Param ( #  Validate input
        [Parameter(Mandatory=$true, Position=0)]
        [ValidatePattern( '^[A-Z0-9@#*]{8}\d$' )] # @#*
        [ValidateScript({$_.Length -eq 9})]
        [string]
        $cusip
    )
    $sum = 0
    0..7 | ForEach { $c = $cusip[$_] ; $v = $null
        if ([Char]::IsDigit($c)) { $v = [char]::GetNumericValue($c) }
        if ([Char]::IsLetter($c)) { $v = [int][char]$c - [int][char]'A' +10 }
        if ($c -eq '*') { $v = 36 }
        if ($c -eq '@') { $v = 37 }
        if ($c -eq '#') { $v = 38 }
        if($_ % 2){ $v += $v }
        $sum += [int][Math]::Floor($v / 10 ) + ($v % 10)
    }
    [int]$checkDigit_calculated = ( 10 - ($sum % 10) ) % 10
    return( $checkDigit_calculated )
}

function Test-IsCUSIP {
    [CmdletBinding()]
    [OutputType([bool])]
    Param (
        [Parameter(Mandatory=$true, Position=0)]
        [ValidatePattern( '^[A-Z0-9@#*]{8}\d$' )]
        [ValidateScript({$_.Length -eq 9})]
        [string]
        $cusip
    )
    [int]$checkDigit_told = $cusip[-1].ToString()
    $checkDigit_calculated = Get-CheckDigitCUSIP $cusip
    ($checkDigit_calculated -eq $checkDigit_told)
}

$data = @"
037833100`tApple Incorporated
17275R102`tCisco Systems
38259P508`tGoogle Incorporated
594918104`tMicrosoft Corporation
68389X106`tOracle Corporation   (incorrect)
68389X105`tOracle Corporation
"@ -split "`n"
$data |%{ Test-IsCUSIP $_.Split("`t")[0] }
Output:

True True True True False True

Procedural

Requires Python 3.6 for the string template literal in the print statement.

#!/usr/bin/env python3

import math

def cusip_check(cusip):
    if len(cusip) != 9:
        raise ValueError('CUSIP must be 9 characters')

    cusip = cusip.upper()
    total = 0
    for i in range(8):
        c = cusip[i]
        if c.isdigit():
            v = int(c)
        elif c.isalpha():
            p = ord(c) - ord('A') + 1
            v = p + 9
        elif c == '*':
            v = 36
        elif c == '@':
            v = 37
        elif c == '#':
            v = 38

        if i % 2 != 0:
            v *= 2

        total += int(v / 10) + v % 10
    check = (10 - (total % 10)) % 10
    return str(check) == cusip[-1]

if __name__ == '__main__':
    codes = [
            '037833100',
            '17275R102',
            '38259P508',
            '594918104',
            '68389X106',
            '68389X105'
            ]
    for code in codes:
        print(f'{code} -> {cusip_check(code)}')

Output:

037833100 -> True
17275R102 -> True
38259P508 -> True
594918104 -> True
68389X106 -> False
68389X105 -> True

Composition of pure functions

Works with: Python version 3.7

Composing a set of pure functions, including a number of general and reusable abstractions:

'''CUSIP'''

from itertools import (cycle, islice, starmap)
from functools import (reduce)
from operator import (add)
from enum import (Enum)


# isCusip :: Dict -> String -> Bool
def isCusip(dct):
    '''Test for the validity of a CUSIP string in the
       context of a supplied dictionary of char values'''
    def go(s):
        ns = [dct[c] for c in list(s) if c in dct]
        return 9 == len(ns) and (
            ns[-1] == (
                10 - (
                    sum(zipWith(
                        lambda f, x: add(*divmod(f(x), 10))
                    )(cycle([identity, double]))(
                        take(8)(ns)
                    )) % 10
                )
            ) % 10
        )
    return go


# cusipCharDict :: () -> Dict Char Int
def cusipCharDict():
    '''Dictionary of integer values for CUSIP characters'''
    def kv(a, ic):
        i, c = ic
        a[c] = i
        return a
    return reduce(
        kv,
        enumerate(
            enumFromTo('0')('9') + (
                enumFromTo('A')('Z') + list('*&#')
            )
        ),
        {}
    )


# TEST -------------------------------------------------
# main :: IO ()
def main():
    '''Tests'''

    # cusipTest :: String -> Bool
    cusipTest = isCusip(cusipCharDict())

    print(
        tabulated('Valid as CUSIP string:')(
            cusipTest
        )([
            '037833100',
            '17275R102',
            '38259P508',
            '594918104',
            '68389X106',
            '68389X105'
        ])
    )

# GENERIC -------------------------------------------------


# double :: Num -> Num
def double(x):
    '''Wrapped here as a function for the zipWith expression'''
    return 2 * x


# enumFromTo :: Enum a => a -> a -> [a]
def enumFromTo(m):
    '''Enumeration of values [m..n]'''
    def go(x, y):
        t = type(m)
        i = fromEnum(x)
        d = 0 if t != float else (x - i)
        return list(map(
            lambda x: toEnum(t)(d + x),
            range(i, 1 + fromEnum(y))
        ) if int != t else range(x, 1 + y))
    return lambda n: go(m, n)


# fromEnum :: Enum a => a -> Int
def fromEnum(x):
    '''Index integer for enumerable value.'''
    return ord(x) if str == type(x) else (
        x.value if isinstance(x, Enum) else int(x)
    )


# mul :: Num -> Num -> Num
def mul(x):
    '''Function version of (*) operator;
       a curried equivalent of operator.mul'''
    return lambda y: x * y


# identity :: a -> a
def identity(x):
    '''The identity function.
       The usual 'id' is reserved in Python.'''
    return x


# tabulated :: String -> (a -> b) -> [a] -> String
def tabulated(s):
    '''heading -> function -> input List -> tabulated output string'''
    def go(f, xs):
        def width(x):
            return len(str(x))
        w = width(max(xs, key=width))
        return s + '\n' + '\n'.join([
            str(x).rjust(w, ' ') + ' -> ' + str(f(x)) for x in xs
        ])
    return lambda f: lambda xs: go(f, xs)


# take :: Int -> [a] -> [a]
# take :: Int -> String -> String
def take(n):
    '''The prefix of xs of length n,
       or xs itself if n > length xs.'''
    return lambda xs: (
        xs[0:n]
        if isinstance(xs, list)
        else list(islice(xs, n))
    )


# toEnum :: Type -> Int -> a
def toEnum(t):
    '''Enumerable value from index integer'''
    dct = {
        int: int,
        float: float,
        str: chr,
        bool: bool
    }
    return lambda x: dct[t](x) if t in dct else t(x)


# zipWith :: (a -> b -> c) -> [a] -> [b] -> [c]
def zipWith(f):
    '''Zipping with a custom (rather than tuple) function'''
    return lambda xs: lambda ys: (
        list(starmap(f, zip(xs, ys)))
    )


# MAIN ---
if __name__ == '__main__':
    main()
Output:
Test for validity as a CUSIP string:

'037833100' -> True
'17275R102' -> True
'38259P508' -> True
'594918104' -> True
'68389X106' -> False
'68389X105' -> True
  [ -1 split 0 peek char 0 -
    swap 0 swap 
    witheach
      [ [ dup char 0 char 9 1+ within iff
            [ char 0 - ] done
          dup char A char Z 1+ within iff
            [ char A - 10 + ] done
          dup char * = iff
            [ drop 36 ] done
          dup char @ = iff
            [ drop 37 ] done
          dup char # = iff
            [ drop 38 ] done
          $ "Unexpected character '" swap
          join $ "' in CUSIP." join fail ]
        i^ 1 & if [ 2 * ]
        10 /mod + + ]
    10 mod 10 swap - 10 mod = ]            is cusip ( $ --> b )
    
  [ dup echo$ cusip iff
      [ say " is correct." ]
    else [ say " is incorrect." ]
    cr ]                                   is task  ( $ -->   )
               
  $ "037833100 17275R102 38259P508 594918104 68389X106 68389X105" 
  nest$ witheach task
Output:
037833100 is correct.
17275R102 is correct.
38259P508 is correct.
594918104 is correct.
68389X106 is incorrect.
68389X105 is correct.

R

Follows the same logic as the pseudocode, but rewritten in a more functional/vectorised style.

cusip_checkdigit <- function(s) {
  chars <- strsplit(s, "") |> unlist()
  1:8 |> sapply(
    function(n) {
      char <- chars[n]
      res <- (1 + (n%%2 == 0)) * {
        if (grepl("[0-9]", char)) as.numeric(char)
        else if (grepl("[A-Z]", char)) 9 + which(LETTERS == char)
        else switch(char, "*" = 36, "@" = 37, "#" = 38)
      }
      res%/%10 + res%%10
    }
  ) |> sum() |> (function(x) (10 - (x%%10)) %% 10)()
}

cusip_isvalid <- function(s) {
  if (nchar(s) != 9) {
    stop("CUSIP must have exactly 9 characters")
  }
  checksum <- cusip_checkdigit(s) |> as.character()
  ifelse(endsWith(s, checksum), "Valid CUSIP", "Invalid CUSIP")
}

test_cusips <- c(
  "037833100", "17275R102", "38259P508", "594918104", "68389X106", "68389X105"
)
sapply(test_cusips, cusip_isvalid) |> print(quote = FALSE)
Output:
    037833100     17275R102     38259P508     594918104     68389X106     68389X105 
  Valid CUSIP   Valid CUSIP   Valid CUSIP   Valid CUSIP Invalid CUSIP   Valid CUSIP 
#lang racket
(require srfi/14)

(define 0-char (char->integer #\0))
(define A-char (char->integer #\A))

(define (cusip-value c)  
  (cond
    [(char-set-contains? char-set:digit c)
     (- (char->integer c) 0-char)]
    [(char-set-contains? char-set:upper-case c)
     (+ 10 (- (char->integer c) A-char))]
    [(char=? c #\*) 36]
    [(char=? c #\@) 37]
    [(char=? c #\#) 38]))

(define (cusip-check-digit cusip)
  (modulo
   (- 10
      (modulo
       (for/sum
        ((i (sequence-map add1 (in-range 8))) (c (in-string cusip)))
         (let* ((v (cusip-value c)) (v′ (if (even? i) (* v 2) v)))
           (+ (quotient v′ 10) (modulo v′ 10)))) 10)) 10))

(define (CUSIP? s)
  (char=? (string-ref s (sub1 (string-length s)))
          (integer->char (+ 0-char (cusip-check-digit s)))))

(module+ test
  (require rackunit)         
  (check-true (CUSIP? "037833100"))
  (check-true (CUSIP? "17275R102"))
  (check-true (CUSIP? "38259P508"))
  (check-true (CUSIP? "594918104"))
  (check-false (CUSIP? "68389X106"))
  (check-true (CUSIP? "68389X105")))

no output indicates all tests passed.

(formerly Perl 6)

Works with: Rakudo version 2017.01
sub divmod ($v, $r) { $v div $r, $v mod $r }
my %chr = (flat 0..9, 'A'..'Z', <* @ #>) Z=> 0..*;

sub cuisp-check ($cuisp where *.chars == 9) {
    my ($code, $chk) = $cuisp.comb(8);
    my $sum = [+] $code.comb.kv.map: { [+] (($^k % 2 + 1) * %chr{$^v}).&divmod(10) };
    so (10 - $sum mod 10) mod 10 eq $chk;
}

# TESTING
say "$_: ", $_.&cuisp-check for <
037833100
17275R102
38259P508
594918104
68389X106
68389X105
>
Output:
037833100: True
17275R102: True
38259P508: True
594918104: True
68389X106: False
68389X105: True
Rebol [
    title: "Rosetta code: CUSIP"
    file:  %CUSIP.r3
    url:   https://rosettacode.org/wiki/CUSIP
]

cusip?: function [
    "Validate a CUSIP number using its check digit."
    cusip [string!]
][
    if 9 != length? cusip [
        return false                              ;; CUSIP must be 9 characters
    ]

    sum: 0
    repeat i 8 [                                  ;; skip last (check) digit
        c: cusip/:i
        v: case [
            all [c >= #"0" c <= #"9"] [c - #"0"]  ;; numeric character
            c = #"*" [36]
            c = #"@" [37]
            c = #"#" [38]
            'else    [c - #"A" + 10]              ;; A=10, B=11, ...
        ]
        if even? i [v: v * 2]                     ;; double odd-position digits
        sum: sum + (v // 10) + (v % 10)           ;; sum the two decimal digits of v
    ]
    (#"0" + (10 - (sum % 10) % 10)) == last cusip
]

foreach cusip [
    "037833100" "17275R102" "38259P508"
    "594918104" "68389X106" "68389X105"
][
    print [as-green cusip "is" pick ["valid" "invalid"] cusip? cusip]
]
Output:
037833100 is valid
17275R102 is valid
38259P508 is valid
594918104 is valid
68389X106 is invalid
68389X105 is valid

idiomatic

/*REXX program validates that the  last digit (the check digit)  of a  CUSIP  is valid. */
@.=
parse arg @.1 .
if @.1=='' | @.1==","  then do;   @.1= 037833100       /* Apple Incorporated            */
                                  @.2= 17275R102       /* Cisco Systems                 */
                                  @.3= 38259P508       /* Google Incorporated           */
                                  @.4= 594918104       /* Microsoft Corporation         */
                                  @.5= 68389X106       /* Oracle Corporation (incorrect)*/
                                  @.6= 68389X105       /* Oracle Corporation            */
                            end

     do j=1  while @.j\='';   chkDig=CUSIPchk(@.j)     /*calculate check digit from func*/
     OK=word("isn't is", 1 + (chkDig==right(@.j,1) ) ) /*validate  check digit with func*/
     say 'CUSIP '    @.j    right(OK, 6)     "valid."  /*display the CUSIP and validity.*/
     end   /*j*/
exit                                             /*stick a fork in it,  we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
CUSIPchk: procedure;  arg x 9;  $=0;                     abc= 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
                                       do k=1  for 8
                                       y=substr(x, k, 1)
                                          select
                                          when datatype(y,'W')  then #=y
                                          when datatype(y,'U')  then #=pos(y, abc) + 9
                                          when          y=='*'  then #=36
                                          when          y=='@'  then #=37
                                          when          y=='#'  then #=38
                                          otherwise  return 0       /*invalid character.*/
                                          end   /*select*/
                                       if k//2==0  then #=#+#       /*K even?  Double it*/
                                       $=$ + #%10 + #//10
                                       end      /*k*/
           return (10- $//10) // 10

output   when using the default input:

CUSPID  037833100     is valid.
CUSPID  17275R102     is valid.
CUSPID  38259P508     is valid.
CUSPID  594918104     is valid.
CUSPID  68389X106  isn't valid.
CUSPID  68389X105     is valid.

conciser function

/*REXX program validates that the  last digit (the check digit)  of a  CUSIP  is valid. */
@.=
parse arg @.1 .
if @.1=='' | @.1==","  then do;   @.1= 037833100       /* Apple Incorporated            */
                                  @.2= 17275R102       /* Cisco Systems                 */
                                  @.3= 38259P508       /* Google Incorporated           */
                                  @.4= 594918104       /* Microsoft Corporation         */
                                  @.5= 68389X106       /* Oracle Corporation (incorrect)*/
                                  @.6= 68389X105       /* Oracle Corporation            */
                            end

     do j=1  while @.j\='';   chkDig=CUSIPchk(@.j)     /*calculate check digit from func*/
     OK=word("isn't is", 1 + (chkDig==right(@.j,1) ) ) /*validate  check digit with func*/
     say 'CUSIP '    @.j    right(OK, 6)     "valid."  /*display the CUSIP and validity.*/
     end   /*j*/
exit                                             /*stick a fork in it,  we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
CUSIPchk: procedure; arg x 9;  $=0;         abc= '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ*@#'
                                      /* [↓]  if  Y  isn' found,  then POS returns zero.*/
                                    do k=1  for 8;   y=substr(x,k,1) /*get a character. */
                                    #=pos(y, abc) - 1                /*get its position.*/
                                    if #   == -1  then return 0      /*invalid character*/
                                    if k//2==  0  then #=#+#         /*K even? double it*/
                                    $=$ + #%10 + #//10
                                    end      /*k*/
          return (10-$//10) // 10

output   is the same as the idiomatic REXX version.

# Project : CUSIP

inputstr = list(6)
inputstr[1] = "037833100"
inputstr[2] = "17275R102"
inputstr[3] = "38259P508"
inputstr[4] = "594918104"
inputstr[5] = "68389X106"
inputstr[6] = "68389X105"
for n = 1 to len(inputstr)
     cusip(inputstr[n])
next

func cusip(inputstr) 
        if len(inputstr) != 9
            see " length is incorrect, invalid cusip"
            return
        ok
        v = 0
        sum = 0
        for i = 1 to 8
             flag = 0
             x = ascii(inputstr[i])
             if x >= ascii("0") and x <= ascii("9")
                v = x - ascii("0")
                flag = 1
             ok
             if x >= ascii("A") and x <= ascii("Z")
                v = x - 55
                flag = 1
             ok
             if x = ascii("*")
                v= 36
                flag = 1
             ok
             if x = ascii("@")
                v = 37
                flag = 1
             ok
             if x = ascii("#")
                v = 38
                flag = 1
             ok
             if flag = 0 
                  see " found a invalid character, invalid cusip" + nl
             ok
             if (i % 2) = 0 
                 v = v * 2
             ok
             sum = sum + floor(v / 10) + v % 10
        next 
        sum = (10 - (sum % 10)) % 10
        if sum = (ascii(inputstr[9]) - ascii("0"))
           see inputstr + " is valid" + nl
        else
           see inputstr + " is invalid" + nl
        ok

Output:

037833100 is valid
17275R102 is valid
38259P508 is valid
594918104 is valid
68389X106 is invalid
68389X105 is valid
Works with: Halcyon Calc version 4.2.7
RPL code Comment
≪ 
   SWAP ROT DUP2 ≤ OVER 5 ROLL ≤ AND 
   SWAP NUM ROT NUM - 1 + 0 IFTE
≫ 'BTWEEN' STO

≪  
   0
   1 8 FOR j
      OVER j DUP SUB → c
      ≪  IF c "0" "9" BTWEEN
         THEN LAST 1 - 
         ELSE IF c "A" "Z" BTWEEN
              THEN LAST 
              9 + 
              ELSE IF "*@#" c POS 
                   THEN LAST 35 + 
         END END END
         j 2 MOD SWAP DUP DUP + IFTE
         10 / LAST MOD SWAP IP + +
      ≫ NEXT
  10 SWAP 10 MOD - 10 MOD
  SWAP 9 DUP SUB STR→ ==
≫ 'CUSIP?' STO
BTWEEN ( "char" "from" "to"  -- pos )
evaluate "from" ≤ "char ≤ "to"
if yes, return relative position from "from"


CUSIP? ( "CUSIP"  -- boolean )
  sum := 0
  for 1 ≤ i ≤ 8 do
     c := the ith character of cusip
     if c is a digit then
        v := numeric value of the digit c
     else if c is a letter then
        p := ordinal position of c in the alphabet (A=1...)
        v := p + 9
     else if c = "*", "@", "#"  then
        v := 36, 37, 38

     if i is even then v := v × 2
     sum := sum + int ( v div 10 ) + v mod 10
  repeat
get (10 - (sum mod 10)) mod 10
return true if equal to 9th digit

Input:
 ≪ { "037833100" "17275R102" "38259P508" "594918104" "68389X106" "68389X105" } → tests
   ≪ {} 1 tests SIZE FOR n
        tests n GET n CUSIP? "Yes" "No" IFTE + NEXT 
 ≫ ≫ EVAL
Output:
1: { "Yes" "Yes" "Yes" "Yes" "No" "Yes" }
Works with: HP version 48G
« 0 "" → c
  « 1 8 FOR j 
       OVER j DUP SUB 'c' STO
       CASE 
          "0123456789" c POS  THEN c STR→ END
          c "A" ≥ c "Z" ≤ AND THEN c NUM 64 - END
          "*@#" c POS         THEN LASTARG 35 END
          c "Syntax error" DOERR
       END
       j 2 MOD NOT OVER * +
       10 MOD LASTARG / IP + +
    NEXT
    10 SWAP 10 MOD - 10 MOD
    SWAP 9 DUP SUB STR→ ==
 » » 'CUSIP?' STO
{ "037833100" "17275R102" "38259P508" "594918104" "68389X106" "68389X105" } 1 « CUSIP? ok KO IFTE » DOLIST
Output:
1: { ok ok ok ok KO ok }

Following pseudocode

#!/usr/bin/env ruby

def check_cusip(cusip)
  abort('CUSIP must be 9 characters') if cusip.size != 9

  sum = 0
  cusip.split('').each_with_index do |char, i|
    next if i == cusip.size - 1
    case
    when char.scan(/\D/).empty?
      v = char.to_i
    when char.scan(/\D/).any?
      pos = char.upcase.ord - 'A'.ord + 1
      v = pos + 9
    when char == '*'
      v = 36
    when char == '@'
      v = 37
    when char == '#'
      v = 38
    end

    v *= 2 unless (i % 2).zero?
    sum += (v/10).to_i + (v % 10)
  end

  check = (10 - (sum % 10)) % 10
  return 'VALID' if check.to_s == cusip.split('').last
  'INVALID'
end

CUSIPs = %w[
  037833100 17275R102 38259P508 594918104 68389X106 68389X105
]

CUSIPs.each do |cusip|
  puts "#{cusip}: #{check_cusip(cusip)}"
end

Output:

037833100: VALID
17275R102: VALID
38259P508: VALID
594918104: VALID
68389X106: INVALID
68389X105: VALID

More concise

Since it uses methods like chain, to_h, sum, and infinite Range syntax (0..), this needs a Ruby version > 2.5

TABLE = ("0".."9").chain("A".."Z", %w(* @ #)).zip(0..).to_h

def valid_CUSIP?(str)
  sum = str[0..-2].chars.each_slice(2).sum do |c1,c2|
    TABLE[c1].divmod(10).sum + (TABLE[c2]*2).divmod(10).sum
  end
  str[-1].to_i == (10 - (sum % 10)) % 10
end

CUSIPs = %w(037833100 17275R102 38259P508 594918104 68389X106 68389X105)
CUSIPs.each{|cusip| puts "#{cusip}: #{valid_CUSIP? cusip}"}
fn cusip_check(cusip: &str) -> bool {
    if cusip.len() != 9 {
        return false;
    }

    let mut v = 0;
    let capital_cusip = cusip.to_uppercase();
    let char_indices = capital_cusip.as_str().char_indices().take(7);

    let total = char_indices.fold(0, |total, (i, c)| {
        v = match c {
            '*' => 36,
            '@' => 37,
            '#' => 38,
            _ if c.is_digit(10) => c.to_digit(10).unwrap() as u8,
            _ if c.is_alphabetic() => (c as u8) - b'A' + 1 + 9,
            _ => v,
        };

        if i % 2 != 0 {
            v *= 2
        }
        total + (v / 10) + v % 10
    });

    let check = (10 - (total % 10)) % 10;
    (check.to_string().chars().nth(0).unwrap()) == cusip.chars().nth(cusip.len() - 1).unwrap()
}

fn main() {
    let codes = [
        "037833100",
        "17275R102",
        "38259P508",
        "594918104",
        "68389X106",
        "68389X105",
    ];
    for code in &codes {
        println!("{} -> {}", code, cusip_check(code))
    }
}

Output:

037833100 -> True
17275R102 -> True
38259P508 -> True
594918104 -> True
68389X106 -> False
68389X105 -> True
Output:

See it running in your browser by ScalaFiddle (JavaScript, non JVM) or by Scastie (JVM).

object Cusip extends App {

  val candidates = Seq("037833100", "17275R102", "38259P508", "594918104", "68389X106", "68389X105")

  for (candidate <- candidates)
    printf(f"$candidate%s -> ${if (isCusip(candidate)) "correct" else "incorrect"}%s%n")

  private def isCusip(s: String): Boolean = {
    if (s.length != 9) false
    else {
      var sum = 0
      for (i <- 0 until 7) {
        val c = s(i)
        var v = 0
        if (c >= '0' && c <= '9') v = c - 48
        else if (c >= 'A' && c <= 'Z') v = c - 55 // lower case letters apparently invalid
        else if (c == '*') v = 36
        else if (c == '@') v = 37
        else if (c == '#') v = 38
        else return false
        if (i % 2 == 1) v *= 2 // check if odd as using 0-based indexing
        sum += v / 10 + v % 10
      }
      s(8) - 48 == (10 - (sum % 10)) % 10
    }
  }

}
#!/usr/local/bin/snobol4 -r
*  cusip.sno
*   -- Committee on Uniform Security Identification Procedures
*  -r : read data placed after the end label.
*  Verify check digit and size of cusip code.

     define("cusipt()i")                  :(cusipt_end)
cusipt
     chars = &digits &ucase "*@#"
     cusipt = table()
     i = 0
cusipt_1
     chars pos(i) len(1) . c              :f(return)
     cusipt[c] = i
     i = i + 1                            :(cusipt_1)
cusipt_end

     define("check_cusip(line)c,i")       :(check_cusip_end)
check_cusip
     eq(size(line), 9)                    :f(freturn)
     check_cusip = 0
     i = 0
check_cusip_1
     line pos(i) len(1) . c
     value = t[c]
     value = eq(remdr(i, 2), 1) t[c] * 2
     check_cusip = check_cusip + (value / 10) + remdr(value, 10)
     i = lt(i, 7) i + 1                   :s(check_cusip_1)
     check_cusip = remdr(10 - remdr(check_cusip, 10), 10)
     eq(substr(line, 9, 1), check_cusip)  :s(return)f(freturn)
check_cusip_end

*** main ***
     t = cusipt()

read line = input                         :f(end)
     check_cusip(line)                    :f(bad_cusip)
     output = line " valid."              :(read)
bad_cusip
     output =  line " not valid."         :(read)
end
037833100
17275R102
38259P508
594918104
68389X106
68389X105
68389X10
68389X1059
68389x105
Output:
037833100 valid.
17275R102 valid.
38259P508 valid.
594918104 valid.
68389X106 not valid.
68389X105 valid.
68389X10 not valid.
68389X1059 not valid.
68389x105 not valid.
struct CUSIP {
  var value: String

  private static let alphabet = Array("ABCDEFGHIJKLMNOPQRSTUVWXYZ")

  init?(value: String) {
    if value.count == 9 && String(value.last!) == CUSIP.checkDigit(cusipString: String(value.dropLast())) {
      self.value = value
    } else if value.count == 8, let checkDigit = CUSIP.checkDigit(cusipString: value) {
      self.value = value + checkDigit
    } else {
      return nil
    }
  }

  static func checkDigit(cusipString: String) -> String? {
    guard cusipString.count == 8, cusipString.allSatisfy({ $0.isASCII }) else {
      return nil
    }

    let sum = cusipString.uppercased().enumerated().reduce(0, {sum, pair in
      let (i, char) = pair
      var v: Int

      switch char {
      case "*":
        v = 36
      case "@":
        v = 37
      case "#":
        v = 38
      case _ where char.isNumber:
        v = char.wholeNumberValue!
      case _:
        v = Int(char.asciiValue! - 65) + 10
      }

      if i & 1 == 1 {
        v *= 2
      }

      return sum + (v / 10) + (v % 10)
    })

    return String((10 - (sum % 10)) % 10)
  }
}

let testCases = [
  "037833100",
  "17275R102",
  "38259P508",
  "594918104",
  "68389X106",
  "68389X105"
]

for potentialCUSIP in testCases {
  print("\(potentialCUSIP) -> ", terminator: "")

  switch CUSIP(value: potentialCUSIP) {
  case nil:
    print("Invalid")
  case _:
    print("Valid")
  }
}
Output:
037833100 -> Valid
17275R102 -> Valid
38259P508 -> Valid
594918104 -> Valid
68389X106 -> Invalid
68389X105 -> Valid

Direct translation of pseudocode

proc ordinal-of-alpha {c} {                     ;#  returns ordinal position of c in the alphabet (A=1, B=2...)
    lsearch {_ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z} [string toupper $c]
}

proc Cusip-Check-Digit {cusip} {                ;# algorithm Cusip-Check-Digit(cusip) is
    if {[string length $cusip] != 8} {          ;#    Input: an 8-character CUSIP
        return false
    }
    
    set sum 0                                   ;#    sum := 0
    for {set i 1} {$i <= 8} {incr i} {          ;#    for 1 ≤ i ≤ 8 do
        set c [string index $cusip $i-1]        ;#       c := the ith character of cusip
        if {[string is digit $c]} {             ;#       if c is a digit then
            set v $c                            ;#          v := numeric value of the digit c
        } elseif {[string is alpha $c]} {       ;#       else if c is a letter then
            set p [ordinal-of-alpha $c]         ;#          p := ordinal position of c in the alphabet (A=1, B=2...)
            set v [expr {$p + 9}]               ;#          v := p + 9
        } elseif {$c eq "*"} {                  ;#       else if c = "*" then
            set v 36                            ;#          v := 36
        } elseif {$c eq "@"} {                  ;#       else if c = "@" then
            set v 37                            ;#          v := 37
        } elseif {$c eq "#"} {                  ;#       else if c = "#" then
            set v 38                            ;#          v := 38
        }                                       ;#       end if
        if {$i % 2 == 0} {                      ;#       if i is even then
            set v [expr {$v * 2}]               ;#          v := v × 2
        }                                       ;#       end if

        incr sum [expr {$v / 10 + $v % 10}]     ;#       sum := sum + int ( v div 10 ) + v mod 10
    }                                           ;#    repeat

    expr {(10 - ($sum % 10)) % 10}              ;#    return (10 - (sum mod 10)) mod 10
}
proc check-cusip {cusip} {
    set last  [string index $cusip end]
    set cusip [string range $cusip 0 end-1]
    expr {$last eq [Cusip-Check-Digit $cusip]}
}

More idiomatic Tcl

proc check-cusip {code} {
    if {[string length $code] != 9} {
        return false
    }
    set alphabet 0123456789abcdefghijklmnopqrstuvwxyz@#
    set code [split [string tolower $code] ""]
    foreach char $code idx {1 2 3 4 5 6 7 8 9} {
        set v [string first $char $alphabet]
        if {$v == -1} {return false}
        if {$idx % 2 == 0} {
            incr v $v
        }
        set v [::tcl::mathop::+ {*}[split $v ""]]
        incr sum $v
    }
    expr {$sum % 10 == 0}
}

Common test harness

proc test {} {
    foreach {cusip name} {
        037833100       "Apple Incorporated"
        17275R102       "Cisco Systems"
        38259P508       "Google Incorporated"
        594918104       "Microsoft Corporation"
        68389X106       "Oracle Corporation   (incorrect)"
        68389X105       "Oracle Corporation"
    } {
        puts [format %-40s%s $name [expr {[check-cusip $cusip] ? "valid" : "invalid"}]]
        puts [format %-40s%s $name [expr {[cusip-check $cusip] ? "valid" : "invalid"}]]
    }
}
test

Output

Output:
Apple Incorporated                      valid
Cisco Systems                           valid
Google Incorporated                     valid
Microsoft Corporation                   valid
Oracle Corporation   (incorrect)        invalid
Oracle Corporation                      valid
Translation of: Go
fn is_cusip(s string) bool {
    if s.len != 9 { return false }
    mut sum := 0
    for i in 0..8 {
        c := s[i]
        mut v :=0
        match true {
            c >= '0'[0] && c <= '9'[0] {
                v = c - 48
			}
            c >= 'A'[0] && c <= 'Z'[0] {
                v = c - 55
			}
            c == '*'[0] {
                v = 36
			}
            c == '@'[0] {
                v = 37
			}
            c == '#'[0] {
                v = 38
			}
            else {
                return false
			}
        }
        if i % 2 == 1 { v *= 2 }  // check if odd as using 0-based indexing
        sum += v/10 + v%10
    }
    return int(s[8]) - 48 == (10 - (sum%10)) % 10
}
 
fn main() {
    candidates := [
        "037833100",
        "17275R102",
        "38259P508",
        "594918104",
        "68389X106",
        "68389X105",
	]
 
    for candidate in candidates {
        mut b :=' '
        if is_cusip(candidate) {
            b = "correct"
        } else {
            b = "incorrect"
        }
        println("$candidate -> $b")
    }
}
Output:
037833100 -> correct
17275R102 -> correct
38259P508 -> correct
594918104 -> correct
68389X106 -> incorrect
68389X105 -> correct
Translation of: Go
var isCusip = Fn.new { |s|
    if (s.count != 9) return false
    var sum = 0
    for (i in 0..7) {
        var c = s[i].bytes[0]
        var v
        if (c >= 48 && c <= 57) { // '0' to '9'
            v = c - 48
        } else if (c >= 65 && c <= 90) { // 'A' to 'Z'
            v = c - 55
        } else if (s[i] == "*") {
            v = 36
        } else if (s[i] == "@") {
            v = 37
        } else if (s[i] == "#") {
            v = 38
        } else {
            return false
        }
        if (i%2 == 1) v = v * 2 // check if odd as using 0-based indexing
        sum = sum + (v/10).floor + v%10
    }
    return s[8].bytes[0] - 48 == (10 - (sum%10)) % 10
}

var candidates = [
    "037833100",
    "17275R102",
    "38259P508",
    "594918104",
    "68389X106",
    "68389X105"
]
for (candidate in candidates) {
    var b = (isCusip.call(candidate)) ? "correct" : "incorrect"
    System.print("%(candidate) -> %(b)")
}
Output:
037833100 -> correct
17275R102 -> correct
38259P508 -> correct
594918104 -> correct
68389X106 -> incorrect
68389X105 -> correct
string 0;               \use zero-terminated strings

func    Valid(Cusip);   \Return 'true' if valid CUSIP code
char    Cusip;
int     Sum, I, C, V;
[Sum:= 0;
for I:= 0 to 8-1 do
        [C:= Cusip(I);
        ChOut(0, C);
        case of
          C>=^0 & C<=^9: V:= C-^0;
          C>=^A & C<=^Z: V:= C-^A+10;
          C=^*: V:=36;
          C=^@: V:=37;
          C=^#: V:=38
        other V:= -1;
        if I&1 then V:= V*2;
        Sum:= Sum + V/10 + rem(0);
        ];
C:= Cusip(I);
ChOut(0, C);
V:= rem( (10-rem(Sum/10)) / 10 );
return V = C-^0;
];

int Cusip, N;
[Cusip:= ["037833100",
          "17275R102",
          "38259P508",
          "594918104",
          "68389X106",
          "68389X105"];
for N:= 0 to 6-1 do
        [Text(0, if Valid(Cusip(N))
                then " is valid"
                else " is invalid");
        CrLf(0);
        ];
]
Output:
037833100 is valid
17275R102 is valid
38259P508 is valid
594918104 is valid
68389X106 is invalid
68389X105 is valid
!ys-0

# CUSIP check-digit: for each of 8 chars get a value (digits 0-9,
# letters A=10..Z=35, * = 36, @ = 37, # = 38). Double the even
# positions, sum (v/10 + v%10), check digit = (10 - sum%10) % 10.

defn main():
  cases =: +
    [['037833100' 'Apple']
     ['17275R102' 'Cisco']
     ['38259P508' 'Google']
     ['594918104' 'Microsoft']
     ['68389X106' 'Oracle']
     ['68389X105' 'Oracle']]

  each c cases:
    code =: c.0
    name =: c.$
    ok =: code:cusip-valid?
    tag =: ok.if('valid  ' 'invalid')
    say: "$code  $tag  $name"

defn- cusip-valid?(code):
  body =: str.apply(butlast(code))
  given =: str(code.$)
  (code.# == 9) &&:
    given == str(check-digit(body))

defn- check-digit(s8):
  pairs =: map(vector (1 .. 8) s8)
  sum =:
    reduce \(+ _1 score(_2)) 0: pairs
  mod: (10 - mod(sum 10)) 10

defn- score(pair):
  i =: pair.0
  c =: pair.$
  v =: c:char-value
  v2 =: even?(i).if((2 * v) v)
  (v2 // 10) +: v2 % 10

defn- char-value(c):
  code =: int(c)
  cond:
    (code >= 48) && (code <= 57): code - 48
    (code >= 65) && (code <= 90): code - 55
    code == 42: 36
    code == 64: 37
    code == 35: 38
    else: 0
Output:
$ ys cusip.ys
037833100  valid    Apple
17275R102  valid    Cisco
38259P508  valid    Google
594918104  valid    Microsoft
68389X106  invalid  Oracle
68389X105  valid    Oracle
Translation of: Wren
fn is_cusip(s: string) -> bool {
    if strlen(s) != 9 { return false; }
    let sum = 0;
    for i in 0..8 {
        let c = s[i];
        let v: int;
        match c {
            48..=57 => { v = c - 48; },  // '0' to '9'
            65..=90 => { v = c - 55; },  // 'A' to 'Z'
            '*'     => { v = 36; },
            '@'     => { v = 37; },
            '#'     => { v = 38; },
            _       => { return false; }
        }
        if i % 2 == 1 { v = v * 2; } // check if odd as using 0-based indexing
        sum += (v / 10) +  v % 10;
    }
    return s[8] - 48 == (10 - (sum % 10)) % 10;
}

fn main() {
    let candidates = [
        "037833100",
        "17275R102",
        "38259P508",
        "594918104",
        "68389X106",
        "68389X105"
    ];
    for candidate in candidates {
        let b = is_cusip(candidate) ? "correct" : "incorrect";
        println "{candidate} -> {b}";
    }
}
Output:
037833100 -> correct
17275R102 -> correct
38259P508 -> correct
594918104 -> correct
68389X106 -> incorrect
68389X105 -> correct
const std = @import("std");
const print = std.debug.print;

pub fn CusipCheckDigit(cusip: *const [9:0]u8) bool {
    var i: usize = 0;
    var sum: i32 = 0;
    while (i < 8) {
        const c = cusip[i];
        var v: i32 = undefined;
        if (c <= '9' and c >= '0') {
            v = c - 48;
        }
        else if (c <= 'Z' and c >= 'A') {
            v = c - 55;
        }
        else if (c == '*') {
            v = 36;
        }
        else if (c == '@') {
            v = 37;
        }
        else if (c == '#') {
            v = 38;
        }
        else {
            return false;
        }
        if (i % 2 == 1) {
            v *= 2;
        }
        sum = sum + @divFloor(v, 10) + @mod(v, 10);
        i += 1;
    }
    return (cusip[8] - 48 == @mod((10 - @mod(sum, 10)), 10));
}

pub fn main() void {
    const cusips = [_]*const [9:0]u8 {
        "037833100",
        "17275R102",
        "38259P508",
        "594918104",
        "68389X106",
        "68389X105"
    };
    for (cusips) |cusip| {
        print("{s} -> {}\n", .{cusip, CusipCheckDigit(cusip)});
    }
}
fcn cusipCheckDigit(cusip){
   var [const] vs=[0..9].chain(["A".."Z"],T("*","@","#")).pump(String);
   try{
      sum:=Walker.cycle(1,2).zipWith(fcn(n,c){ v:=vs.index(c)*n; v/10 + v%10 },
           cusip[0,8]).reduce('+);
      ((10 - sum%10)%10 == cusip[8].toInt()) and cusip.len()==9
   }catch{ False }
}
foreach cusip in (T("037833100", "17275R102",
		    "38259P508", "594918104", "68389X106", "68389X105")){
   println(cusip,": ",cusipCheckDigit(cusip));      
}
Output:
037833100: True
17275R102: True
38259P508: True
594918104: True
68389X106: False
68389X105: True