#include <iostream>
#include <sstream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <cstring>
#include <string>
#include <vector>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <algorithm>
#include <functional>

using namespace std;

class lInt
{
private:
	vector<int> place;
public:
	lInt( string number )
	{
		for ( unsigned int i = 0; i < number.length(); i++ )
		{
			place.push_back( number[i] - '0' );
		}

		reverse( place.begin(), place.end() );

		return;
	}

	void printNumber()
	{
		if ( place.size() < 79 )
		{
			for ( vector<int>::reverse_iterator it = place.rbegin(); it != place.rend(); it++ )
			{
				cout << *it;
			}
		}
		else
		{
			cout << "overflow";
		}

		cout << endl;

		return;
	}

	void operator += ( string number )
	{
		vector<int> buffer;
		
		for ( unsigned int i = 0; i < number.length(); i++ )
		{
			buffer.push_back( number[i] - '0' );
		}
		reverse( buffer.begin(), buffer.end() );

		for ( unsigned int i = 0; i < buffer.size(); i++ )
		{
			if ( i < place.size() )
			{
				place[i] += buffer[i];
			}
			else
			{
				place.push_back( buffer[i] );
			}
		}
		
		for ( unsigned int i = 0; i < place.size(); i++ )
		{
			if ( 10 <= place[i] )
			{
				if ( i + 1 < place.size() )
				{
					place[i + 1] += place[i] / 10;
				}
				else
				{
					place.push_back( place[i] / 10 );
				}

				place[i] %= 10;
			}
		}
	}
};

int main()
{
	int n;
	string buffer;

	cin >> n;

	for ( int i = 0; i < n; i++ )
	{
		cin >> buffer;
		lInt li( buffer );
		cin >> buffer;
		li += buffer;

		li.printNumber();
	}

	return 0;
}