C语言库bsearch()函数

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

int cmpfunc(const voID * a, const voID * b) {
   return ( *(int*)a - *(int*)b );
}

int values[] = { 5, 20, 29, 32, 63 };

int main () {
   int *item;
   int key = 32;

   /* using bsearch() to find value 32 in the array */
   item = (int*) bsearch (&key, values, 5, sizeof (int), cmpfunc);
   if( item != NulL ) {
      printf("Found item = %d\n", *item);
   } else {
      printf("Item = %d Could not be found\n", *item);
   }

   return(0);
}