Python: Printing variables and strings in same line

Question

I am currently trying to make a program that will print if variable a is divisible by variable b. I keep running into errors when trying to print the values a and b.

My code:

a, b = eval(input('Input a list of 2 numbers: '))
a = str(a)
b = str(b)
if (a % b == 0):
    print ( a + 'is divisible by' + b)
else:
    print( a + 'is not divisible by' + b)

Error message:

Traceback (most recent call last): File "C:/Users/Noah/Documents/Python/Assignment 4 Question 7.py", line 4, in if (a % b == 0): TypeError: not all arguments converted during string formatting

Answer 1

This is because you are casting a and b to strings. You're most likely putting them in as int, which they should be. If for some reason you aren't, then the casts should be a = int(a), etc.

Also eval is to be avoided, you could change this to:

a = input('insert a number')
b = input('insert another number')

Or if you aboslutely have to enter them at once, you could do

a, b = input('Insert two numbers separated by commas').split(',')

Just make sure to not have spaces between them, or, to be safe, when casting you can do

a = int(a.strip())

Answer 2

There are a few problems with this.

a, b = eval(input('Input a list of 2 numbers: '))

don't use eval() for a few more years. Even then use with extreme caution.

a = str(a)
b = str(b)

str() turns whatever is in there into a string which makes...

if (a % b == 0):  #this is where your error is

impossible to do because the "%" modulo operator is expecting numbers on either side. Since these are supposed to be numbers try wrapping a and b in int() or float() statements

a = input('Input the first number: ')
b = input('Input the second number: ')
a = int(a)
b = int(b)
if (a % b == 0):
    print( a + 'is divisible by' + b)
else:
    print( a + 'is not divisible by' + b)