#include <fstream>
using namespace std;
ifstream fin("cifra.in");
ofstream fout("cifra.out");
int main(){
    int n;
    fin >> n;
    for(int i = 1; i <= n; i++){
        int s = 0;
        int x;
        fin >> x;
        for(int k = 1; k <= x; k++){
            int p = 1;
            for(int j = 1; j <= k; j++){
                p *= j;
                p = p%10;
            }
            s += p;
            s %= 10;
        }
        fout << s << endl;
    }
}