#include<fstream>

using namespace std;

int megold(int n)
{
	int a = n % 10;
	for (int i = 1; i < n; i++)
	{
		a = ((a % 10) * (n % 10)) % 10;
	}
	return a;
}

int main()
{
	ifstream in("cifra.in");
	ofstream out("cifra.out");
	int n; in >> n;
	for (int i = 0; i < n; i++)
	{
		int m; in >> m;
		int ossz = 0;
		for(int j=1; j <= m;j++)
		{
			ossz += megold(j);
		}
		if (ossz >= 10) out << ossz % 10 << endl; else out << ossz<<endl;
	}
	
	return 0;
}