#include <bits/stdc++.h>
using namespace std;

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

int a[20] = {1, 4, 7, 6, 5, 6, 3, 6, 9, 0, 1, 6, 3, 6, 4, 6, 7, 4, 9, 0};

int main() {
    int t;
    fin >> t;
    while(t--) {
        string s;
        fin >> s;
        if(s.size() == 1) s = "0" + s;
        int n = s.size();
        int x = (s[n - 2] - '0') * 10 + (s[n - 1] - '0');
        int rem = x % 20;
        int ans = 0;
        for(int i = 0; i < rem; i++) {
            ans += a[i];
        }
        fout << (ans % 10) << '\n';
    }
}