#include <iostream>
#include <fstream>

using namespace std;

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

int main()
{
    int t, n, suma = 0, k;
    fin >> t;
    for (int i = 1; i <= t; i++)
    {
        suma = 0;
        fin >> n;
        for (int j = 1; j <= n; j++)
        {
            k = (j * j) % 10;
            suma = suma + k;
        }
        fout << suma % 10;
    }
    return 0;
}