二分查找,一直黑屏无显示


#include<stdio.h>
int binary_search(int a[],int k,int s)
{
    int left=0;
    int right=s-1;
    int mid=(left+right)/2;
    while(left<=right)
    {
        if (a[mid]<k)
        left=mid+1;
        else if(a[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 key=7;
    int sz=sizeof(arr)/sizeof(arr[0]);
    int ret=binary_search(arr,key,sz);
    if (ret==-1)
    printf("找不到");
    else
    printf("找到了,下标是%d",ret); 
    
return 0;    
} 

img

计算 mid 放到while循环里