插入排序

降序排列数组

function insertionSort(arr) {
  let len = arr.length;
  for (let i = 1; i < len; i++) {
    const temp = arr[i];
    let j = i;
    for (j; j > 0 && arr[j - 1] < temp; j--) {
      arr[j] = arr[j - 1];
    }
    arr[j] = temp;
  }
  return arr;
}

算法测试

console.log(insertionSort([3, 6, 1, 8, 9, 5]));
// [ 9, 8, 6, 5, 3, 1 ]
console.log(insertionSort([-3, 7, -8, 4, 6, -5, -4, 5]));
// [ 7, 6, 5, 4, -3, -4, -5, -8 ]
console.log(insertionSort([12, 0, 3, -4, 3, 78]));
// [ 78, 12, 3, 3, 0, -4 ]