#include "bits/stdc++.h"

using namespace std;

int putere (int c1, int c2)
{
    int r = 1;
    for ( int a = 0; a < c2; a++) {
        r = r * c1;
        r %= 10;
    }
    return r;
}

int main()
{
    ifstream cin("cifra.in");
    ofstream cout("cifra.out");
    int t;
    cin >> t;
    vector<string> v(t);
    for(int i = 0; i < t; i++) {
        cin >> v[i];
    }
    for (int i = 0; i < t; i++) {
        if(v[i].size() == 1) {
            v[i] = "0" + v[i];
        }
        string s = v[i].substr(v[i].size() - 2, v[i].size());
        int n = stoi(s);
        int c = 0;
        for (int e = 1; e <= n; e++) {
            c += putere(e, e);
            c%=10;
        }
        cout << c << '\n';
    }
    return 0;
}