#include<iostream.h>
#include<fstream.h>
#include<math.h>
fstream in ("cifra.in",ios::in), out("cifra.out",ios::out);
int cifra(int n)
{ int i,j,x,s=0;
for(i=1;i<=n;i++){
	x=1;
	for(j=1;j<=i;j++)
		x=(x%10)*(i%10);
	s=s%10+x%10;
		}
return s%10;
}
main(){
int n,v[30000],i;
in>>n;
for(i=1;i<=n;i++){
	in>>v[i];
	cout<<endl;}
for(i=1;i<=n;i++)
	out<<cifra(v[i])<<endl;
}