#include <iostream>
#include <fstream>
using namespace std;
int x,s,i,j,y,b;

int main()
{
    long int a;
    ifstream f("cifra.in");
    ofstream g("cifra.out");
    f>>a;
    x=1;
    for(i=1;i<=a;i++)
    {
        f>>b;
        for(j=1;j<=b;j++)
        {
            for(y=1;y<=j;y++)
            {
                x=x*j;
            }
            s=s+x%10;
            x=1;
        }
        g<<s%10<<endl;
        s=0;

    }
    f.close();
    g.close();

    return 0;
}