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

ifstream fin("cifra.in");
ofstream fout("cifra.out");

int uc[100];

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

void precalc()
{
    for(int i = 1; i <= 99; i++)
        uc[i] = (uc[i - 1] + ucif(i)) % 10;
}

int main()
{
    int T, nrc, x;
    char n[101];
    precalc();
    fin >> T;
    fin.get();
    while(T--)
    {
        fin.getline(n, 100);
        nrc = strlen(n);
        x = n[nrc - 1] - '0';
        if(nrc > 1)
            x += 10 * (n[nrc - 2] - '0');
        fout << uc[x] << '\n';
    }
    fin.close();
    fout.close();
    return 0;
}