三种排序算法及三种变量交换的宏实现

1、快速排序 #include <stdio.h> #include <string.h> #include <stdlib.h> #define N 100 #define SWAP(x,y)                    \ {                                               \        int t;t=(x);(x)=(y);(y)=t;    \ }     int partition(int a[],int l,int r); void quick_sort(int a[],int l,int r);     int main(int argc,char *argv[]) {        int a[N],n,i;        memset(a,0,sizeof(a));        printf("Enter how many numbers \n");        scanf("%d",&n);        for(i=0;i<n;i++)               scanf("%d",a+i);        printf("before sorted:\n");        for(i=0;i<n;i++)               printf("%d\t",a[i]);        printf("\n");        quick_sort(a,0,n-1);        printf("after sorted:\n");        for(i=0;i<n;i++)               printf("%d\t",a[i]);        printf("\n");        system("pause");        return 0; } void quick_sort(int a[],int l,int r) {        int i;        if(r<=l)return;        i=partition(a,l,r);        quick_sort(a,l,i-1);        quick_sort(a,i+1,r);        return ; }     int partition(int a[],int l,int r) {        int i,j,v;        i=l-1;        j=r;        v=a[r];        for(;;)        {               while(a[++i]<v);               while(v<a[--j])if(j==l)break;               if(j<=i)break;               SWAP(a[i],a[j]);        }        SWAP(a[i],a[r]);        return i; } 2、冒泡排序 #include <stdio.h> #include <stdlib.h> #include <string.h> #define N 100 #define SWAP(a, b)  {(a) ^= (b); (b) ^= (a); (a) ^= (b);}     int main() {        int num,a[N],i,j;        memset(a,0,sizeof(a));        printf("Enter  how many elements in the array?\n");        scanf("%d",&num);        for(i=0;i<num;i++)                scanf("%d",a+i);        printf("before sorted:\n");        for(i=0;i<num;i++)                printf("%d\t",a[i]);        printf("\n");        for(i=num-1;i>0;i--)                      for(j=0;j<i;j++)                      {                 if(a[j]>a[j+1])                                    SWAP(a[j],a[j+1]);             }        printf("after sorted:\n");        for(i=0;i<num;i++)                printf("%d\t",a[i]);        printf("\n");           system("pause");        return 0; } 3、选择排序 #include <stdio.h> #include <stdlib.h> #include <string.h> #define N 100 #define SWAP(x,y,t) ((t)=(x),(x)=(y),(y)=(t))     int a[N],n=0;     void sort_a(); void p_a();     int main() {        int i=0;        memset(a,0,sizeof(a));        printf("How many int numbers?\n");        scanf("%d",&n);        if(n<1 || n>N)        {               printf("can't accept\n");               return 1;        }        else        {               for(i=0;i<n;i++)                      scanf("%d",a+i);        }        printf("before sorted:\n");        p_a();        sort_a();        printf("after sorted\n");        p_a();        system("pause");        return 0; }     void p_a() {        int i=0;        for(i=0;i<n-1;i++)               printf("%d\t",a[i]);                    printf("%d\n",a[i]); }     void sort_a() {        int i,j,min,temp;        for(i=0;i<n-1;i++)        {               min=i;               for(j=i;j<n;j++)               {                      if(a[j]<a[min])                             min=j;               }               if(min!=i)                      SWAP(a[min],a[i],temp);        } } -------------------------------------------- 简单测试结果: How many int numbers? 6 13      7       19      5       29      31 before sorted: 13      7       19      5       29      31 after sorted 5       7       13      19      29      31 请按任意键继续. . . 作者Blog：http://blog.csdn.net/fxsjy/