#include <string.h>
#include <stdlib.h>
#include <iostream>
#pragma warning(disable:4996)
using namespace std;
int t,x,v[1000],i,S,j;
int ultima_cifra(int n)
{
    int i, p = 1;
    for (i = 1; i <= n; i++)
        p = (p * n) % 10;
    return p;
}
void citire()
{
    cin >> t;
    for (i = 1; i <= t; i++)
    {
        cin >> x; S = 0;
        for (j = 1; j <= x; j++)
        {
            S =( S + ultima_cifra(j)) % 10;
        }
        v[i] = S;
    }
}
void afisare()
{
    for (i = 1; i <= t; i++)
        cout << v[i] << endl;
}
int main()
{
    citire();
    afisare();
    return 0;
}