#include <fstream>
using namespace std;

const int D[][10] =
{
    {0,1,5,2,8,3,9,2,8,7},
    {0,1,7,0,6,1,7,4,8,7}
};

int toInt(char c)
{
    return c-'0';
}

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

    int T;
    fin >> T;

    int Ans;
    string s;
    while(T--) {
        fin >> s;
        if(s.size() == 1) {
            Ans = D[0][toInt(s[0])];
        }
        else {
            Ans = toInt(s[s.size()-2]) * 7 % 10;
            Ans += D[toInt(s[s.size()-2])%2^1][toInt(s[s.size()-1])];
            Ans %= 10;
        }
        fout << Ans << "\n";
    }
}