#include <fstream.h>
int main ()
{int a[10],n,i,j,nr,cifra,c;
ifstream f ("cifra.in");
ofstream g ("cifra.out");
for (i=1;i<=9;i++) a[i]=1;
for (i=1;i<=9;i++)
 for (j=1;j<=i;j++)
  a[i]=(a[i]*i)%10;
f>>n;
for (i=1;i<=n;i++)
{
  f>>c;
  cifra=0;
  for (j=1;j<=c;j++)
   {
    nr=j%10;
    cifra=(cifra+a[nr])%10;
   }
   g<<cifra<<'\n';
}
return 0;}