#include <fstream>
#include <iostream>
#include <cstring>
using namespace std;
ifstream f("cifra.in");
ofstream g("cifra.out");
char N[102];
int v[22] = {0,1, 4, 7, 6, 5, 6, 3, 6, 9, 0, 1, 6, 3, 6, 5, 6, 7, 4, 9, 0};
int u2cif()
{
    int nr = 0, lg = strlen(N);
    if(lg == 1)
        nr = N[0] - '0';
    else
        nr = (N[lg - 2] - '0') * 10 + N[lg - 1] - '0';
    return nr;
}
int main()
{
    int T;
    f >> T;
    for(int i = 1; i <= T; i++)
    {
        f >> N;
        int u = u2cif();
        //cout<<u<<endl;
        int cc = u / 20, rr = u % 20, sr = 0;
        for(int j = 1; j <= rr; j++)
            sr += v[j];
            //cout<<cc<<' '<<rr<<' '<<sr<<endl;
        int uc = (cc * 4 + sr) % 10;
        g << uc << '\n';
    }
    return 0;
}