交换排序

Posted 2021-01-31 wzqstudy

#include "stdio.h"
#define MAXSIZE 20
typedef int ElemType;
typedef struct
{
    ElemType r[MAXSIZE+1];
    int length;
}SortList;

/*
冒泡排序：BubbleSort
*/

void BubbleSort(SortList *L)
{
    int i,j;ElemType t;
    for(i=1;i<L->length;i++)            //排序趟数
        for(j=1;j<=L->length-i;j++)        //每趟比较的次数
            if(L->r[j]>L->r[j+1])
            {
                t = L->r[j];
                L->r[j] = L->r[j+1];
                L->r[j+1] = t;
            }
}

//改进算法
void BubbleSort(SortList *L)
{
    int i,j; ElemType t;
    int flag = 1;
    for(i=1;flag&&i<L->length;i++)
        for(flag=0,j=1;j<=L->length-i;j++)
            if(L->r[j]>L->r[j+1])
            {
                t = L->r[j];
                L->r[j] = L->r[j+1];
                L->r[j+1] = t;
                flag = 1;                    //有交换，则置交换标记为真，需要进行下趟排序
            }
}



//快速排序
void HoareSort(SortList *L,int low,int high)
{
    int i,j;
    if(low<high)
    {
        i = low; j = high;
        L->r[0] = L->r[i];
        while(i<j)
        {
            while(i<j&&L->r[j]>=L->r[0])j--;    
            L->r[i] = L->r[j];
            while(i<j&&L->r[i]<L->r[0])i++;
            L->r[j]=L->r[i];
        }
        L->r[i]=L->r[0];
        HoareSort(L,low,i-1);
        HoareSort(L,i+1,high);
    }
}
void QuickSort(SortList *L)
{
    HoareSort(L,1,L->length);
}