LeetCode: Minimum Number Of Swaps To Make The Binary String Alternating Solution

1/**
2 * @param {string} s
3 * @return {number}
4 */
5var minSwaps = function (s) {
6  const N = s.length
7  const count = (s, c) => s.split("").filter(_c => _c === c).length
8  const [count1, count0] = [count(s, "1"), count(s, "0")]
9  const valid = Math.abs(count1 - count0) <= 1
10
11  if (!valid) {
12    return -1
13  }
14
15  const calculateSwaps = (s, nextMatch) => {
16    let swaps = 0
17    for (const c of s) {
18      if (c !== nextMatch) {
19        swaps++
20      }
21      nextMatch = nextMatch === "1" ? "0" : "1"
22    }
23    return swaps >> 1
24  }
25
26  if (count1 > count0) {
27    return calculateSwaps(s, "1")
28  } else if (count0 > count1) {
29    return calculateSwaps(s, "0")
30  } else {
31    return Math.min(calculateSwaps(s, "1"), calculateSwaps(s, "0"))
32  }
33}