#include <iostream>
#include<fstream>
using namespace std;
int cifra(int n)
{
    long S=0,k=1,b,f,i;
    for(i=1;i<=n;i++)
    {
        k=i;
        b=k;
        f=i;
            k--;
            while(k!=0)
            {
               k--;
                b=b*f;
            }
    S=S+b;
    }
return S%10;
}
int main ()
{
    ifstream f("cifra.in");
    ofstream g("cifra.out");
    int c,a[100],j;
    f>>c;
    for(j=1;j<=c;j++)
    {
        f>>a[j];
        g<<cifra(a[j])<<endl;
    }
}