#include <fstream>

using namespace std;

int ultima_cifra(long int a)
{
	int nr_zeci;
	int nr_cifre, u_cifra;
	//int c[10][4]={{0,0,0,0},{1,1,1,1},{6,2,4,8},{1,3,9,7},{6,4,6,4},{5,5,5,5},{6,6,6,6},{1,7,9,3},{6,8,4,2},{1,9,1,9}};
	int s[10] = {0, 1, 5, 2, 8, 3, 9, 2, 8, 7};
	a = a%100;
	nr_zeci = a/10;
	nr_cifre = a%10;
	u_cifra = (nr_zeci*5+s[nr_cifre])%10;
	return u_cifra;
}

int main()
{
	int T,i;
	long int N;
	ifstream f("cifra.in");
	ofstream g("cifra.out");
	f>>T;
	for (i = 1; i <= T; i++)
	{
		f>>N;
		g<<ultima_cifra(N)<<'\n';
	}
	f.close();
	g.close();
	return 0;
}