* NOTE : this IS possible also, this isn't a trick question
OK; so this is the thing :
You go into a hotel with only 9 rooms,
If you can see there is only 1 entrance/exit
if you can't it's the little box on room number 1
you have to go to EVERY room
but you can only go to every room only once.
the 1 is the ONLY room you can go through twice
[because it is the entrance and the exit]
you can't go diagonal.
you can't go retracing;
if you go through the hotel like through room 1 4 7 8 3 6 5 2 3 2 1
you can't go through ANY of those rooms again but 1;
This is VERY difficult!
As entertaining as this may be for some, it is not an English grammar question, unless you're focusing on the difference between "going to a room" and "going through a room".
I see a way of doing it if I can go to a room (other than 1) twice, but not through it twice!
Just a little note:
This thread was originally posted in the grammar forum, but I moved it over here to the puzzle area.
I haven't tried to solve the puzzle yet, but I imagine someone will manage to do it!
Have fun. Emotion: smile
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I think puzzle instructions need to be precise.

Don't you need to say you have to go to EVERY room and then leave the hotel?

Clivend then leave the hotel?
It's easy if you don't have to leave the hotel. Is that the trick?
1 4 7 8 9 6 5 2 3
As stated and assuming you have to start and leave at 1, I don't believe this is possible. There are very few alternative strategies and the game is quickly analysed.
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As I understand the instructions you're only supposed to enter every room.
But nowhere says you have to make your way back to 1 again. So maybe it is a trick
question after all. And if so I'd pick 1 2 5 4 7 8 9 6 3.