#include <iostream>
#include <cmath>
using namespace std;
 
#include <boost/multiprecision/cpp_int.hpp>
using namespace boost::multiprecision;
 
#define CINT cpp_int 
 
int main() {
    int n; cin >> n; CINT a, b; 
    CINT REF = pow(CINT(10), 80);
    for (int i = 0; i < n; i++) {
        cin >> a >> b;
        if (a + b >= REF) cout << "overflow" << endl;
        else cout << a + b << endl;
    }
    return 0;
}
