#include <iostream>
#include <cmath>

using namespace std;

int main() {
	int n;
	cin >> n;

	unsigned long long a, b;
	for (int i = 0; i < n; i++) {
		cin >> a >> b;
		a += b;

		if (a / pow(10, 80) >= 1) {
			cout << "overflow";
		}
		else {
			cout << a;
		}
		cout << endl;
	}
	return 0;
}