program cch(input,output,f1,f2);
var
 f1,f2:text;
 head,tail,q,i,n:integer;
 x:longint;
 a:array[1..10] of longint;
procedure empty;
begin
 head:=0; tail:=0;
end;

procedure inqueue(x:longint);
begin
 if tail=10 then writeln(f2,'queue out')
    else begin
     if head=0 then head:=1;
     inc(tail);
     a[tail]:=x;
    end;
end;
procedure outqueue;
begin
 if head=0 then writeln(f2,'queue empty')
           else inc(head);
end;
procedure print;
var
 i:integer;
begin
 if head=0 then exit;
 writeln(f2,tail-head+1);
 for i:=head to tail-1 do write(f2,a[i],' ');
 writeln(f2,a[tail]);
end;

begin
 assign(f1,'queue.in');
 assign(f2,'queue.out');
 reset(f1);
 rewrite(f2);
 readln(f1,n);
 for i:=1 to n do begin
  read(f1,q);
  case q of
  1:empty;
  2:begin readln(f1,x);
         inqueue(x);
    end;
  3:outqueue;
  4:print;
  end;
 end;
 close(f1);
 close(f2);
end.