# [Community Puzzle] Tree Paths

https://www.codingame.com/training/easy/tree-paths

Created by @gareve,validated by @Pduhard,@LastRick and @kayou.
If you have any issues, feel free to ping them.

I donâ€™t understand why are the tags DFS and BFS added to this puzzle. Neither of such search is necessary.

3 Likes

I said as much during submission. It looks like a tree but you could solve it without.

The puzzle is fun but I think the description is misdirecting the coders into building binary trees. So far all solutions in C++ except one (and mine) did a variant of a binary tree (with relation parent -> children) and then had troubles finding the path as they start from root. Much easier solution is to store reverse relations (child -> parent).

Maybe call it â€śreverse binary tree lookupâ€ť or a bit more enigmatic: â€śBacktracingâ€ť? Or put a hint in the description?

At least maybe this will point to another possible solution.

The hint is in the fact that itâ€™s an easy puzzle.

To be fair I usually ignore tags and go with my own ideas. If Iâ€™m stuck then sure tags can help, but since this is an easy puzzle you can find a simple solution of your own.

2 Likes

Hey guys
I have trouble passing validators 1 and 2, despite the fact that other validators and all provided unit tests are OKâ€¦ do you know what behavior are these two testing please?
Thanks!

EDIT
Nevermind, nailed it

2 Likes

Do you guys know what validators 1 and 2 are? I seem to keep failing on them. Thank you

1 Like

Validators 1 and 2 are exactly identical to testcases 1 and 2 except that nodes are labelled differently.
Maybe your problem is that you assume that the root is always labelled 1 in your algorithm ?

4 Likes

I pass every test and every validator except validator 4 and I have no idea why

Hard to say â€¦ But i can give you 2 more tests similar to this validator

``````9
6
4
1 3 2
2 4 5
3 9 8
8 7 6

Left Right Right
``````

and

``````9
6
4
1 3 2
2 4 5
3 8 9
8 7 6

Left Left Right``````
4 Likes

Thanks so much.
validator 4 was the only case with a tree with more than a root parent having the target in the last input line.
I overwrote my loop index in a way that would always skip the last iteration and the root was handled as a special case.

Hello everyone,
I pass every test, but when i submitted my code, Validator 2 and 3 was wrong.
I have no idea why â€¦ Is there some personalized test i can get, for debug ?

Thanks a lot !

Ah merchi pour les tests additionnels (+50XP :-)), jâ€™avais fait un sorted(directions, reverse=True) au lieu de direction.reverse(), en gros je rajoutais un tri Ă  la con lol

Hello,
despite all the tests validations are OK, i only got 40% success in final tests. Is there any suggestion I can improve my understanding of current issues please ?

Which validators are failing?
Check your code agains case like this:

``````11
10
5
1 2 3
2 4 5
3 9 8
8 6 7
6 10 11
``````

` Right Right Left Left`

1 Like

Hi, I only validate tests 3 and 5. will try your example

ok, changed my way of using it (list instead of table of nodes), got my 100% ! thank !