Radix Sort

function radixSort(arr) {
  const max = Math.max(...arr);
  let divisor = 1;
  while (divisor < max) {
    const buckets = new Array(10).fill().map(() => []);
    for (let i = 0; i < arr.length; i++) {
      const bucketIndex = Math.floor((arr[i] / divisor) % 10);
      buckets[bucketIndex].push(arr[i]);
    }
    arr = buckets.flat();
    divisor *= 10;
  }
  return arr;
}