#include <iostream>
#include <string>
using namespace std;

short rasp[99];
string s;

int p(int cifra, int putere)
{
	int rez = 1;
	for (int i = 1; i <= putere; ++i)
		rez = (rez*cifra)%10;
	return rez;
}

void calculare()
{
	for (int i = 1; i <= 99; ++i)
		rasp[i] = (rasp[i-1] + p(i%10,i))%10;
}

short u2cs()
{
	if (s.size() == 1)
		return s[0] - '0';
	return (s[s.size()-1] - '0') * 10 + s[s.size()] - '0';
}

void citire_si_raspundere()
{
	int t;
	scanf("%d\n",&t);
	for (int i = 1; i <= t; ++i)
	{
		getline(cin,s);
		printf("%d\n",rasp[u2cs()]);
	}
}

int main()
{
	freopen("cifra.in","r",stdin);
	freopen("cifra.out","w",stdout);
	calculare();
	citire_si_raspundere();
	return 0;
}