#include <fstream>

using namespacde std;

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

int main() {
    int T;
    fin >> T;

    for (int test = 0; test < T; test++) {
        string N;
        fin >> N;

        int lungime = N.length();
        int uc2 = 0;

        if (lungime == 1) {
            uc2 = N[0] - '0';
        } else {
            int penultima = N[lungime - 2] - '0';
            int ultima = N[lungime - 1] - '0';
            uc2 = penultima * 10 + ultima;
        }

        int suma = 0;

        for (int i = 1; i <= uc2; ++i) {
            int baza = i % 10;
            int exponent = i;
            int produs = 1;

            for (int j = 0; j < exponent; ++j) {
                produs = (produs * baza) % 10;
            }

            suma = (suma + produs) % 10;
        }

        fout << suma << "\n";
    }

    return 0;
}