#942 - DI String Match

Easy • View on LeetCode • View on GitHub

Problem Description

A permutation perm of n + 1 integers of all the integers in the range [0, n] can be represented as a string s of length n where:

s[i] == 'I' if perm[i] < perm[i + 1], and
s[i] == 'D' if perm[i] > perm[i + 1].

Given a string s, reconstruct the permutation perm and return it. If there are multiple valid permutations perm, return any of them.

Solution

/**
 * @param {string} s
 * @return {number[]}
 */
var diStringMatch = function(s) {
  const result = [];
  let low = 0;
  let high = s.length;

  for (const char of s) {
    if (char === 'I') {
      result.push(low);
      low++;
    } else {
      result.push(high);
      high--;
    }
  }

  result.push(low);
  return result;
};