力扣上，我把你的代码照抄过去，运行显示不通过。
public int binarySearch(int num){
int left = 1;
int right = num;
while(true){
if(left == right){
return left;
}
int mid = left + (right - left)/2;
int res = binarySearch(mid);
if(res == 0){
return mid;
}
if(res == 1){
left = mid + 1;
}else{
right = mid;
}
}
}
