#include<algorithm>
#include<iostream>
#include<cstdio>
#include<stdio.h>
#include<string>
#include<string.h>
#include"stdafx.h"
using namespace std;

int main()
{
	char a1,a2  ;
	long long a, b,c;
	int kaisu = 0;
	cin >> kaisu;
	for (int i = 0; i < kaisu; i++)
	{
		cin >> a;
		cin >> b;
		a1 =  GetDigit(a);
		a2 = GetDigit(a);
		if (a1 + a2 >= 80) { printf("overflow"); }
		else { c = a + b; printf(c + "\n"); }
	}
	return 0;
}
unsigned GetDigit(unsigned num) {
	return std::to_string(num).length();
}