Why my solution is wrong for problem evil hacker

My solution is-

#include <iostream>
using namespace std;
int main() {
	int A,X,Y;
	cin >> A;
	for (int i = 0; i < A; i++) {
		cin >> X >> Y;
		cout << (X/2) + (Y/2) + 1 << "\n";

But I am getting wrong answer. Is it formatting related.

Be careful about the extreme values of X and Y. What about X and/or Y being equal to 0?!

Contest not ended, I don’t think that is a good idea to give big hints like this.