#include <iostream>
#include <fstream>
#include <cstring>
using namespace std;
ifstream f("cifra.in");
ofstream g("cifra.out");

int U[100];

int ucif(int n)
{
    int uc = n % 10, r = n % 4, p = 1;
    if(r == 0)
        r = 4;
    while(r--)
        p *= uc;
    return p % 10;
}

void precalcul()
{
    for(int i = 1; i < 100; i++)
        U[i] = (U[i - 1] + ucif(i)) % 10;
}

int main()
{
    int T, ncif, rest;
    char sir[101];
    precalcul();
    f >> T;
    while(T--)
    {
        f >> sir;
        ncif = strlen(sir);
        rest = sir[ncif - 1] - '0';
        if(ncif >= 2)
            rest += (sir[ncif - 2] - '0') * 10;
        g << U[rest] << '\n';
    }
    f.close();
    g.close();
    return 0;
}