1544. Make The String Great

make_the_string_great.py

class Solution:
    def makeGood(self, s: str) -> str:
        if len(s) <= 1:
            return s

        stack = []

        for char in s:
            if (stack and stack[-1] != char
                and stack[-1].lower() == char.lower()):
                stack.pop()
            else:
                stack.append(char)

        return "".join(stack)