#include <fstream>
#include <cstring>

using namespace std;

ifstream fin("cifra.in");
ofstream fout("cifra.out");

char c[105], util[2];
int nrteste, nrcif, rez;

int main()
{
    fin >> nrteste;
    fin.getline(c, 5);
    while (nrteste)
    {
        fin.getline(c, 102);
        if (strlen(c) > 1)
        {
            strcpy(util, c+strlen(c)-2);
            switch (util[1]){
            case 48:
                rez = util[0] * 7 % 10;
                break;
            case 1+48:
                rez = util[0] * 7 % 10 + 1;
                break;
            case 2+48:
                rez = util[0] * 7 % 10  + 4;
                break;
            case 3+48:
                rez = util[0] * 7 % 10 + 2;
                break;
            case 4+48:
                rez = util[0] * 7 % 10 + 8;
                break;
            case 5+48:
                rez = util[0] * 7 % 10 + 3;
                break;
            case 6+48:
                rez = util[0] * 7 % 10  + 9;
                break;
            case 7+48:
                rez = util[0] * 7 % 10 + 2;
                break;
            case 8+48:
                rez = util[0] * 7 % 10 + 8;
                break;
            case 9+48:
                rez = util[0] * 7 % 10 + 7;
                break;
            }
            fout << rez % 10<< '\n';
        }
        else
        {
            util[0] = c[0];
            switch (util[0]){
            case 0+48:
                rez = 0;
                break;
            case 1+48:
                rez = 1;
                break;
            case 2+48:
                rez = 4;
                break;
            case 3+48:
                rez = 2;
                break;
            case 4+48:
                rez = 8;
                break;
            case 5+48:
                rez = 3;
                break;
            case 6+48:
                rez = 9;
                break;
            case 7+48:
                rez = 2;
                break;
            case 8+48:
                rez = 8;
                break;
            case 9+48:
                rez = 7;
                break;
            }
        }

        nrteste--;
    }
    return 0;
}