#include <fstream>
#include <string>

using namespace std;

const int K = 20;

int u_cif[K+1];

int ultima_cifra_suma(int n)
{
    return ((n / K) * u_cif[K] + u_cif[n%K]) % 10;
}

int main()
{
    for (int i = 1; i <= K; i++)
    {
        int p = 1;
        for (int j = 0; j < i; j++)
        {
            p = (p * i) % 10;
        }
        u_cif[i] = (u_cif[i-1] + p) % 10;
    }
    ifstream in("cifra.in");
    ofstream out("cifra.out");
    int t;
    in >> t;
    for (int i = 0; i < t; i++)
    {
        string s;
        in >> s;
        if (s.length() >= 2)
        {
            s = s.substr(s.length() - 2);
        }
        int n = stoi(s);
        out << ultima_cifra_suma(n) << "\n";
    }
    in.close();
    out.close();
    return 0;
}