#include <iostream>
#include <cstring>
#include <fstream>
using namespace std;

int U[101];

int ucif(int n)
{
    int exp = n % 4, nr = n % 10, put = 1;
    if(exp == 0)
        exp = 4;
    for(int i = 1; i <= exp; i++)
        put *= nr;
    return put % 10;
}

void precalcul()
{
    U[0] = 0;
    for(int i = 1; i < 100; i++)
        U[i] = (U[i - 1] + ucif(i)) % 10;
}

int main()
{
    ifstream cin("cifra.in");
    ofstream cout("cifra.out");
    int n;
    char sir[101];
    precalcul();
    cin >> n;
    while(n--)
    {
        cin >> sir;
        int nrcif = strlen(sir);
        int rest = sir[nrcif - 1] - '0';
        if(nrcif >= 2)
            rest += (sir[nrcif - 2] - '0') * 10;
        cout << U[rest] << '\n';
    }
    return 0;
}