二分查找非递归与递归实现

#include <stdio.h>
int  BinSearch(int *str, int sz, int key)   //非递归
{

    int left = 0;
    int right = sz-1;
    int mid;
    while (left <= right)
    {
         mid = (left + right) / 2;
         if (key < str[mid])
         {  
             right = mid-1;

         }
         if (key > str[mid])
         {
             left = mid+1;

         }
         if (key == str[mid])
             return str[mid];

    }
    printf("no this key\n");
    return 0;
}

//int BinSearch(int *str, int left,int right ,int key)//mid的作用域
//{
//  if (left <= right)
//  {
//      int mid = (left + right) / 2;
//      if (key == str[mid])
//          return str[mid];
//      if (key < str[mid])
//          return BinSearch(str,left,mid-1,key);
//      if (key > str[mid])
//          return BinSearch(str,mid+1,right,key);
//     }
//  printf("No  this key\n");
//  return 0;
//
//}
int main()
{
    int arr[] = { 1, 2, 3, 4, 5, 6, 7, 8 };
    int sz = sizeof(arr) / sizeof arr[0];
    int p = BinSearch(arr, 0,sz-1, 10);
    printf("%d\n", p);

    return 0;

}