#include <fstream>
#include <cstring>

using namespace std;

ifstream f("cifra.in");
ofstream g("cifra.out");
int u[101];

int ucif(int n) {
    int r = n % 4, p = 1, uc = n % 10;
    if(r == 0) r = 4;
    while(r--)
        p *= uc;
    return p % 10;
}
void precalc() {
    for(int i = 1; i < 100; i++)
        u[i] = (u[i - 1] + ucif(i)) % 10;
}

int main() {
    int t, nrcif, rest;
    char sir[101];
    precalc();
    f >> t;
    while(t--)
    {
        f >> sir;
        nrcif = strlen(sir);
        rest = sir[nrcif - 1] - '0';
        if(nrcif >= 2)
            rest += (sir[nrcif - 2] - '0') * 10;
        g << u[rest] << '\n';
    }

    f.close();
    g.close();
    return 0;
}