Reverse_In_Parenthesis.md

🔷 Reverse In Parenthesis 🔷

Challenge description

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

Input/Output

• [execution time limit] 3 seconds (java)

• [memory limit] 1 GB

• [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.

[Java] Syntax Tips

## Solutions:

• JS solution

  CodeSignalSolutions/Reverse_In_Parenthesis/Reverse_in_parenthesis.js

  Lines 1 to 11 in 21bf758

  	function solution(input) {
  	for(let mostNested; (mostNested=findMostNested(input))!=null;){
  	input = input.replace(mostNested, mostNested.substring(1, mostNested.length -1).split('').reverse().join(''))
  	}
  	return input;
  	}
  	function findMostNested(string){
  	const start = string.lastIndexOf("(");
  	return start !== -1 ? string.substring(start, string.indexOf(")", start) + 1) :null;
  	}

  

• Java solution

  CodeSignalSolutions/Reverse_In_Parenthesis/Reverse_in_parenthesis.java

  Lines 15 to 23 in 21bf758

  	static String solution(String input){
  	UnaryOperator<String> mostNestedOperator1 = x -> {
  	int start = x.lastIndexOf('(');
  	return (start != -1) ?x.substring(start, x.indexOf(')', start) + 1) :null; // returns most nested with parenthesis
  	};
  	for(String mostNested; (mostNested = mostNestedOperator1.apply(input)) != null; )
  	input = input.replace(mostNested, new StringBuilder(mostNested.substring(1, mostNested.length() - 1)).reverse().toString());
  	return input;
  	}