#include <fstream>

using namespace std;

int U[]= {0, 1, 5, 2, 8, 3, 9, 2, 8, 7}; /// U[i]=Uc(1^1+2^2+...+i^i)

ifstream f("cifra.in");
ofstream g("cifra.out");

int main()
{
    int T, ncif, gz;
    char sir[101];
    f>>T;
    f.ignore();
    while(T--)
    {
        f.getline(sir, 101);
        //ncif=strlen(sir);
        ncif=f.gcount()-1;
        if(ncif>=2)
            gz=7*(sir[ncif-2]-'0');
        else
            gz=0;
        g<<(gz+U[sir[ncif-1]-'0'])%10<<'\n';
    }

    f.close();
    g.close();
    return 0;
}