快速排序算法的C语言实现

#include <stdlib.h>
#include <stdio.h>

static void swap(void *x,void *y,size_t l) {
   char *a = x,*b = y,c;
   while(l--) {
      c = *a;
      *a++ = *b;
      *b++ = c;
   }
}

static void sort(char *array,size_t size,int (*cmp)(void*,void*),int begin,int end) {
   if (end > begin) {
      void *pivot = array + begin;
      int l = begin + size;
      int r = end;
      while(l < r) {
         if (cmp(array+l,pivot) <= 0) {
            l += size;
         } else {
            r -= size;
            swap(array+l,array+r,size);
         }
      }
      l -= size;
      swap(array+begin,array+l,size);
      sort(array,size,cmp,begin,l);
      sort(array,r,end);
   }
}

void qsort(void *array,size_t nitems,void*)) {
   sort(array,(nitems-1)*size);
}

typedef int type;

int type_cmp(void *a,void *b){ return (*(type*)a)-(*(type*)b); }

main(){ /* simple test case for type=int */
  int num_list[]={5,4,3,2,1};
  int len=sizeof(num_list)/sizeof(type);
  char *sep="";
  int i;
  qsort(num_list,len,sizeof(type),type_cmp);
  printf("sorted_num_list={");
  for(i=0; i<len; i++){
    printf("%s%d",sep,num_list[i]);
    sep=",";
  }
  printf("};n");
}