code signal - 13. reverseInParentheses

Question

Write a function that reverses characters in (possibly nested) parentheses in the input string.

Input strings will always be well-formed with matching ()s.

Example

• For inputString = "(bar)", the output should be reverseInParentheses(inputString) = "rab";
• For inputString = "foo(bar)baz", the output should be reverseInParentheses(inputString) = "foorabbaz";
• For inputString = "foo(bar)baz(blim)", the output should be reverseInParentheses(inputString) = "foorabbazmilb";
• For inputString = "foo(bar(baz))blim", the output should be reverseInParentheses(inputString) = "foobazrabblim". Because "foo(bar(baz))blim" becomes "foo(barzab)blim" and then "foobazrabblim".

Input/Output

• [execution time limit] 4 seconds (py3)

• [input] string inputString

  A string consisting of lowercase English letters and the characters ( and ). It is guaranteed that all parentheses in inputString form a regular bracket sequence.

  Guaranteed constraints: 0 ≤ inputString.length ≤ 50.

• [output] string

  • Return inputString, with all the characters that were in parentheses reversed.

Best_ANSWER

def reverseInParentheses(inputString):
    for i in range(len(inputString)):
        if inputString[i] == "(":
            start = i
        if inputString[i] == ")":
            end = i
            return reverseInParentheses(inputString[:start] + inputString[start+1:end][::-1] + inputString[end+1:])
    return inputString

• 어렵다.... 답을 봄