#include <bits/stdc++.h>

using namespace std;

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

const int v_par[] = {0, 1, 4, 7, 6, 5, 6, 3, 6, 9};
const int v_impar[] = {0, 1, 6, 3, 6, 5, 6, 7, 4, 9};
const int p[] = {0, 7, 4, 1, 8, 5, 2, 9, 6, 3, 0};

int T;
string s;

int main()
{
    in>>T;

    for(int i = 1; i <= T; ++i)
    {
        in>>s;
        int nr = s.size() == 1 ? (s[0] - '0') : (s[s.size() - 2] - '0') * 10 + (s[s.size() - 1] - '0');
        int k = s.size() == 1 ? 0 : p[s[s.size() - 2] - '0'];
        int S = 0;
        for(int j = 1; j <= s[s.size() - 1] - '0'; ++j) S += (k % 2 == 0 ? v_par[j] : v_impar[j]) % 10;
        out<<(S+k) % 10<<"\n";
    }


    return 0;
}