# include<fstream.h>
void main()
{ifstream fi;
ofstream fo;
long int n,uc=1,i,t,c,u,j;
fi.open("cifra.in");
fo.open("cifra.out");
fi>>t;
for(i=1;i<=t;i++){fi>>n;u=0;
		  for(c=1;c<=n;c++){for(j=1;j<=c;j++){uc=(uc*c)%10;}
				    u=(u+uc)%10;uc=1;
				   }
		  fo<<u<<'\n';
		 }
fi.close();
fo.close();
}