SOURCE

function bucketSort (arr) {
  var min = Math.min(...arr);
  var max = Math.max(...arr);
  var result = [];
  var buckets = [];
  // 桶的个数
  var size = 3;
  // 一个桶放几个元素，一个桶至少放一个
  var num = Math.floor((max - min) / size) || 1;
  for (let j = 0; j < arr.length; j++) {
    const val = arr[j];
    // 通过val计算桶偏移量
    const cont = Math.floor((val - min) / size);
    if (!buckets[cont]) {
      buckets[cont] = [];
    }
    buckets[cont].push(val);
  }
  for (const bucket of buckets) {
    console.log(bucket)
    for (let i = 1; i < bucket.length; i++) {
      var current = bucket[i];
      var prevIndex = i - 1;
      // 前面的比后面的大需要往后挪
      while (prevIndex >= 0 && bucket[prevIndex]>current) {
        bucket[prevIndex + 1] = bucket[prevIndex];
        prevIndex--;
      }
      // 补上原来的位置
      bucket[prevIndex + 1] = current;
    }
    console.log(bucket);
    result = result.concat(bucket);
  }
  return result;
}
var a = bucketSort([3, 8, 6, 1, 5, 7, 9, 2, 4]);
console.log(a)