Maximum Number of Pairs in Array LeetCode solution in JavaScript

1
/**
2
 * @param {number[]} nums
3
 * @return {number[]}
4
 */
5
var numberOfPairs = function (nums) {
6
  let pairs = 0;
7
  const s = new Set();
8
  for (const num of nums) {
9
    if (s.has(num)) {
10
      pairs += 1;
11
      s.delete(num);
12
    } else {
13
      s.add(num);
14
    }
15
  }
16
  return [pairs, nums.length - pairs * 2];
17
};