Command "paste - - - - ", how to specify a big column number

Question

In command paste - - - -, numbers of - is equal the future column number. In my case, I have 55,000 future column, for me wont need to put 55,000 - what I will can use?

Example:

title1:A1
title2:A2
title3:A3
title4:A4
title5:A5

title1:B1
title2:B2
title3:B3
title4:B4
title5:B5

title1:C1
title2:C2
title3:C3
title4:C4
title5:C5

title1:D1
title2:D2
title3:D3
title4:D4
title5:D5

I want to transform this file (A) into following:

title1 A1   title1 B1   title1 C1   title1 D1   title2 A2
title2 B2   title2 C2   title2 D2   title3 A3   title3 B3
title3 C3   title3 D3   title4 A4   title4 B4   title4 C4
title4 D4   title5 A5   title5 B5   title5 C5   title5 D5

For this, I used :

$ sed 's/:/ /; /^$/d' sample.txt \
    | sort | paste - - - - -

But in my file, I will have a big column number: 55,000 or 400 column. What is the other form to replace the - ??

Answer 1

String multiplication trick based on this answer: https://stackoverflow.com/a/5349772/4082052

---

Use substitution to insert programmable number of dashes

paste $(for i in {1..400}; do echo -n '- '; done)

or

paste $(printf -- "- %.s" {1..400})

To know why printf -- was used: Dashes in printf

Answer 2

For a file with 4 rows:

 paste $(for((i=1;i<4;i++)); do echo -n "- "; done; echo -n "-") < file