#include<fstream>
using namespace std;
ifstream fin("cifra.in");
ofstream fout("cifra.out");
int n, i, f, t, v[30000], b, j, s, a;
char x;

int main(){
    fin>>t;
    for(i = 1; i <= t; i++){
        fin >> x;
        v[i] = (int)x - 48;
    }
    for(j = 1; j <= t; j++){
        n = v[j];
            s = 0;
            for(a = 1; a <= n; a++){
                f = 1;
                for(i = 1; i <= a; i++){
                    f = (f * a) % 10;
                }
                s = s + f;
            }
            fout << s % 10 << endl;
    }
    return 0;
}