#include <fstream>
#include <math.h>
using namespace std;

int putere (int q, int z, int s)
	{
	s*=q;
	if (z<q) putere (q, z+1,s);
	else return s;
	}
	

int main ()
	{
	ifstream f ("cifra.in");
	ofstream g ("cifra.out");
	int S;
	unsigned int T,n;
	f>>T;
	for (int i=0; i<T; i++)
		{
		f>>n; 
		S=0;
		for (int q=1; q<=n; q++)
			{
			S+=putere(q,1,1)%10;
			}
		g<<S%10<<" ";
		}
	g.close();
	return 0;
	}