How to add space beetween a pair of consecutive letters and not add space beetween two characters th-CodePudding

For example: The string BINGO! should be B I N G O!

I have already tried:

s = "BINGO!"
print(" ".join(s[::1]))

CodePudding user response：

I'd use regex: re.sub(r'(?<=[a-zA-Z])(?=[a-zA-Z])', ' ', 'BINGO!')

This basically says, "for every empty string in 'BINGO!' that both follows a letter and precedes a letter, substitute a space."

CodePudding user response：

I like what esramish had said, however that is a bit overcomplicated for your goal. It is as easy as this:

string = "BINGO"

print(" ".join(string))

This returns your desired output.

CodePudding user response：

You can use a single lookahead to assert a char a-z to the right and make the pattern case insensitive.

In the replacement use the full match and a space using \g<0>

(?i)[A-Z](?=[A-Z])

(?i) Inline modifier for a case insensitive match
[A-Z] Match a single char A-Z
(?=[A-Z]) Positive lookahead, assert a char A-Z to the right of the current position

Example

import re

print(re.sub(r'(?i)[A-Z](?=[A-Z])', '\g<0> ', 'BINGO!'))

Output

B I N G O!