Minimum Operations to Make a Uni-Value Grid LeetCode solution in JavaScript

1
var minOperations = function (grid, x) {
2
  let remainder = -Infinity,
3
    flatten = [],
4
    res = 0;
5

6
  for (let i = 0; i < grid.length; i++) {
7
    for (let j = 0; j < grid[i].length; j++) {
8
      if (remainder === -Infinity) remainder = grid[i][j] % x;
9
      else if (remainder !== grid[i][j] % x) {
10
        return -1;
11
      }
12
      flatten.push(grid[i][j]);
13
    }
14
  }
15
  flatten.sort((a, b) => a - b);
16
  let median = flatten[~~(flatten.length / 2)];
17

18
  for (let i = 0; i < flatten.length; i++) {
19
    res += Math.abs(flatten[i] - median) / x;
20
  }
21
  return res;
22
};