LeetCode: The K Weakest Rows In A Matrix Solution

1/**
2 * @param {number[][]} mat
3 * @param {number} k
4 * @return {number[]}
5 */
6var kWeakestRows = function (mat, k) {
7  return mat
8    .map((r, i) => [r, i])
9    .sort((a, b) => a[0].filter(Boolean).length - b[0].filter(Boolean).length)
10    .slice(0, k)
11    .map(([_, i]) => i)
12}