关于c:冒泡排序

#include <stdio.h>#include <stdlib.h>void display(int* arr, int length){    for (int i = 0; i < length; ++i)    {        printf("%d%s", arr[i], i == length - 1 ? " " : ", ");    }    printf("\n");}void swap(int* a, int* b){    int temp = *a;    *a = *b;    *b = temp; }void bubble(int* arr, int length){    for (int i = 0; i < length - 1; ++i)    {        for (int j = 0; j < length - 1 - i; ++j)        {            if (arr[j] > arr[j + 1]) {                swap(&arr[j], &arr[j + 1]);            }        }    }}int main(int argc, char const *argv[]){    int arr[] = {2, 3, 5, 21, 2, 3, 999, 2, 34, 87};    int length = sizeof(arr) / sizeof(int);    display(arr, length);    bubble(arr, length);    display(arr, length);    return 0;}