#include <iostream>
#include <cstring>
#include <fstream>
using namespace std;

ifstream fin("cifra.in");
ofstream fout("cifra.out");
int v[25];// = {0,1,5,2,8,3,9,2,8,7,7,8,4,7,3,8,4,1,5,4};
int main()
{
    int n, uc;
    string nr;
    v[0]=0;
    for (int i = 1; i <= 20; i++){
        int bi = i, ci = i-1;
        while (ci > 0){
            bi = bi*i;
            ci--;
        }
        v[i] = (v[i-1]+bi%10)%10;
    }
    fin >> n;
    for (int i1 = 0; i1 < n; i1++){
        fin >> nr;
        int len = nr.length();
        if (len >= 2){
            uc = (nr[len - 2]-'0')*10+(nr[len-1]-'0');
        }
        else{
            uc = nr[0]-'0';
        }
        int cat = uc/20;
        uc = uc%20;

        fout << (v[uc]+4*cat)%10 << "\n";
    }
    return 0;
}