#include <iostream>
#include <string>
#include <algorithm>
using namespace std;

int a[81] {0};
int b[81] {0};
int sum[55][81] {0};

int trans(char);

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

    for (int i = 0; i < n; i++)
    {
        string s1, s2;
        cin >> s1 >> s2;
        int l1 = s1.length(), l2 = s2.length();
        for (int j = l1 - 1; j >= 0; j--)
        {
            a[l1-1-j] = trans(s1[j]);
        }
        for (int j = l2 - 1; j >= 0; j--)
        {
            b[l2-1-j] = trans(s2[j]);
        }

        int ll = max(l1, l2);
        for (int j = 0; j < ll; j++)
            sum[i][j] = a[j] + b[j];

        for (int j = 0; j < ll; j++)
        {
            sum[i][j+1] += sum[i][j] / 10;
            sum[i][j] %= 10;
        }


        for (int j = 0; j < 81; j++)
        {
            a[j] = 0;
            b[j] = 0;
        }

    }

    for (int i = 0; i < n; i++)
    {
        if (sum[i][80] > 0)
            cout << "overflow" << endl;
        else
        {
            int j = 80;
            while (sum[i][j] <= 0)
                j--;
            while (j >= 0)
            {
                cout << sum[i][j];
                j--;
            }
            cout << endl;
        }
    }

    return 0;
}

int trans(char ch)
{
    switch (ch)
    {
    case '0':
        return 0;
    case '1':
        return 1;
    case '2':
        return 2;
    case '3':
        return 3;
    case '4':
        return 4;
    case '5':
        return 5;
    case '6':
        return 6;
    case '7':
        return 7;
    case '8':
        return 8;
    case '9':
        return 9;

    }
}