#include <bits/stdc++.h>
#include <cassert>

using namespace std;

fstream f("cifra.in", ios::in);
fstream g("cifra.out", ios::out);
int main(void)
{
    vector<uint32_t> precomp;
    uint32_t n, p = 1, s = 0;
    string szNum;

    precomp.push_back(0);
    assert(f >> n);

    for(uint32_t i = 1; i < 100; i++)
    {
        precomp.push_back(i);
        for(uint32_t j = 1; j < i; j++)
            precomp[i] *= i, precomp[i] %= 10;
        precomp[i] += precomp[i-1], precomp[i] %= 10;
    }

    for(;n ;n--)
    {
        assert(f >> szNum);
        uint16_t len = szNum.length();
        if(len)
            assert(g << precomp[szNum[len-1] - '0'] << "\n");
        else
            assert(g << precomp[((szNum[len - 2] - '0') * 10 + szNum[len - 1]) - '0'] << "\n");
    }

    return EXIT_SUCCESS;
}