var  a:array [0..120] of byte;
     i,x,j,t,e,nr:integer;
     n,c:string;
     f,g:text;
begin
  assign(f,'cifra.in');
  reset(f);
  assign(g,'cifra.out');
  rewrite(g);
  for i:=1 to 99 do
  begin
    x:=1;
    for j:=1 to i do
    begin
      x:=x mod 10;
      x:=x *i;
    end;
    a[i]:=(a[i-1]+x) mod 10;
  end;
  readln(f,t);
  for i:=1 to t do
  begin
    readln(f,n);
    c:=copy(n,length(n)-1,2);
    val(c,nr,e);
    writeln(g,a[nr]);
  end;
  close(f);
  close(g);
end.