#include<fstream.h>
ifstream f("cifra.in");
ofstream g("cifra.out");
double t,n;
int uc,j,i,nr,k;
int main ()
{
f>>t;
for (i=1;i<=t;i++)
    {f>>n;
    uc=0;
    for (j=1;j<=n;j++)
	{nr=1;
	for(k=1;k<=j;k++)
	   nr=nr*(j%10);
	uc=uc+(nr%10);}
	g<<uc%10;}
f.close ();
g.close ();
return 0;}