program InfoArena; {Cifra}
var
  fin,fout:text;
  fv,nrval,n:word;
  s,b,e,j:word;

begin
  assign(fin,'cifra.in');
  reset(fin);
  assign(fout,'cifra.out');
  rewrite(fout);

  readln(fin,nrval);
  for fv:=1 to nrval do begin
    readln(fin,n);
    s:=0;
    for b:=1 to n do begin
      j:=b;
      for e:=2 to b do j:=(j mod 10)*(b mod 10);
      j:=(j mod 10);
      s:=((s+j) mod 10);
    end;
    s:=(s mod 10);
    writeln(fout,s);
  end;
  close(fin);
  close(fout);
end.