交换排序之快速排序

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <time.h>
typedef struct list{
    int *p;
    int len;
}S;
void Initialize(int *&p,int len){
    srand(time(NULL));
    int i;
    for(i=0;i<len;i++){
        p[i] = rand() % 100;
    }
}

int quickchange(int *&p,int low,int high){ //直接交换原理（核心）
    int pivot;
    pivot = p[low];
    while(low<high){ //low = high时循环结束
        while(low<high && pivot<=p[high]){ //一定要加限制条件，因为可能存在最后几个未排序的元素全部都满足pivot<=p[high]，则high会一直减下去直到负数
            high--;
        }
        p[low] = p[high];
        while(low<high && pivot>=p[low]){//不要以为外层循环有low<high，内层就可以不用加，不然high可以一直减下去
            low++;
        }
        p[high] = p[low];

    p[low] = pivot; //p[low] = p[high] = pivot
    }
    return low;
}
void QuickSort(int *&p,int low,int high){
    if(low<high) {
        int pivot;
        pivot = quickchange(p, low, high);
        QuickSort(p, low, pivot - 1);
        QuickSort(p, pivot + 1, high);
    }
}
void SPrint(int *p,int len){
    int i;
    for(i=0;i<len;i++){
        printf("%d ",p[i]);
    }
}
int main(){
    S s;
    s.len = 10;
    s.p = (int *)malloc(sizeof(S)*s.len);
    Initialize(s.p,s.len);
    SPrint(s.p,s.len);
    printf("\n");
    QuickSort(s.p,0,s.len-1);
    SPrint(s.p,s.len);

    return 0;
}