C Binary Search

// w  ww  . j a v  a2  s.  c om
#include<stdio.h>

int binary_search(char *items, int count, char key)
{
  int low, high, mid;

  low = 0; high = count-1;
  while(low <= high) {
    mid = (low+high)/2;
    if(key < items[mid]) 
        high = mid-1;
    else if(key > items[mid]) 
        low = mid+1;
    else 
        return mid; /* found */
  }
  return -1;
}

int main(void){
   char *str = "123456";
  
   int index = binary_search(str, 6, '3');
  
   printf("%d",index);
}