#include<fstream>
#include<string>

using namespace std;

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

const int rep = 20;
string s;
int c[ rep ] = { 0, 1, 4, 7, 6, 5, 6, 3, 6, 9, 0, 1, 6, 3, 6, 5, 6, 7, 4, 9 };

int main() {
    int q, t, uc;
    for( int i = 1; i < rep; ++ i ) {
        c[ i ] += c[ i - 1 ];
    }
    f >> q;
    while ( q -- ) {
        f >> s;
        t = 0;
        uc = 0;
        for( int i = 0; i < ( int )s.size(); ++ i ) {
            uc = (t * 10 + s[ i ] - '0') / rep;
            uc %= 10;
            t = (t * 10 + s[ i ] - '0') % rep;
        }
        g << (uc * c[ rep - 1 ] + c[ t ]) % 10 << "\n";
    }
    return 0;
}