#include<stdio.h>
int binary_search(int arr[],int k,int sz)
{
int left=0;
int right=sz-1;
while(left<=right)
{
int mid=(left+right)/2;
if(arr[mid]<k)
{
left=mid+1;
}
else if(arr[mid]>k)
{
right=mid-1;
}
else
return mid;
}
return -1;
}
int main()
{
int arr[]={1,2,3,4,5,6,7,8,9,10};
int k=7;
int sz=sizeof(arr)/sizeof(arr[0]);
int ret= binary_search(arr, k,sz);
if(ret==-1)
{
printf("找不到指定的数字\n");
}
else
{
printf("找到了，下标是：%d\n",ret);
}
return 0;
}
