#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 precalc(){
    for(int i = 1; i < 100; i++)
        u[i] = (u[i - 1] + ucif(i)) % 10;
}

int main()
{
    int t, ncif, rest;
    char sir[101];
    precalc();
    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';
    }
    return 0;
}