#include <bits/stdc++.h>
using namespace std;

long calculate(long n){
  long sum = 0;
    
  for (long i = 1; i <= n; i++){
    long prod = 1;
    
    for (int j = 0; j < i; j++)
      prod *= (i % 10);
    
    sum += (prod % 10) % 10;
  }
  
  sum %= 10;
  
  return sum;
}

ifstream in("cifra.in");
ofstream out("cifra.out");

int main(){
  long n, sum = 0, temp = 0;

  in >> n;

  while (n--){
    cin >> temp;
    sum = calculate(temp);
    out << sum << "\n";
  }
  
  return 0;
}