int main()
{ int arr[]={1,2,3,4,5,6,7,8,9,10};
int k=3;
int left=0;
int right=strlen(arr)-1;
while(left<=right){
int mid=(left+right)/2;
if (arr[mid]>k)
{ right=mid-1;
}
if(arr[mid]
}
else
{printf("找到了，下标为:%d\n",mid);}
break;
}
if(right>left)
{printf("找不到\n");}
}
arr并不是字符串，不要用strlen函数，直接用sizeof关键字取数组大小