#1190 - Reverse Substrings Between Each Pair of Parentheses

Medium • View on LeetCode • View on GitHub

Problem Description

You are given a string s that consists of lower case English letters and brackets.

Reverse the strings in each pair of matching parentheses, starting from the innermost one.

Your result should not contain any brackets.

Solution

/**
 * @param {string} s
 * @return {string}
 */
var reverseParentheses = function(s) {
  const stack = [[]];

  for (const char of s) {
    if (char === '(') {
      stack.push([]);
    } else if (char === ')') {
      const reversed = stack.pop().reverse();
      stack[stack.length - 1].push(...reversed);
    } else {
      stack[stack.length - 1].push(char);
    }
  }

  return stack[0].join('');
};