关于算法:插入排序C语言

#include <stdio.h>#include <stdlib.h>void mergeSort(int *arr, int len){  for (int j = 1; j < len; j++)  {    int key = arr[j];    int i = j - 1;    while (i >= 0 && arr[i] > key)    {      arr[i + 1] = arr[i];      i--;    }    arr[i + 1] = key;  }}int main(void){  int len = 20;  int *arr = (int *)malloc(len * sizeof(int));  for (int k = 0; k < 20; k++)  {    arr[k] = rand();  }  mergeSort(arr, len);  for (int i = 0; i < len; i++)  {    printf("%d ", arr[i]);  }  printf("\n");  return 0;}