Show HN: A difficult game to test your logic

112 CodeCrusader 53 3/24/2025, 1:47:02 PM rvlabs.ca ↗

Comments (53)

vunderba · 80d ago
Nice implementation. I've seen this puzzle before, does anyone know if it actually has an official name? Kind of reminds me of a variation on the tower of Hanoi.

https://en.wikipedia.org/wiki/Tower_of_Hanoi

CodeCrusader · 80d ago
Thanks! I’m not sure if there’s an official name for it — I originally saw the game a decade ago at my university and just recently decided to build my own take on it. It definitely has some Tower of Hanoi vibes. Let me know if you find an official name for it!
kazinator · 80d ago
Not being able to repeat a successfully solved level sucks.

It would benefit from that model that is popular nowadays whereby higher levels are unlocked by solving lower levels, and you can choose to play any unlocked level whatsoever.

nvader · 80d ago
At first I thought you meant roguelite, but that isn't it.

But now I think a roguelite version of this game could be quite addicting.

No comments yet

AndrewStephens · 80d ago
Very cool implementation of a classic puzzle (with a surprise on the last level that I haven't seen before.)

Years ago I wrote some example Python to solve the same puzzle in another game (with spoilers for level 3):

https://sheep.horse/2011/11/jumping_frogs_-_using_python_to_...

CodeCrusader · 80d ago
Glad you liked it! That last level twist was a fun addition — I wanted to keep things interesting. Your Python solver looks awesome, I’ll definitely check it out. Always cool to see different approaches to the same puzzle!
fractallyte · 80d ago
In some UK schools, this was the basis for a mathematics investigation for 11 year olds. Do the task for various numbers of frogs, records the results, and try to find a rule - then make a prediction for a certain number, and test it!

A great introduction to the Scientific Method, and a fun activity too.

Here's an example: https://spiremaths.co.uk/wp-content/uploads/Frogs.pdf

CodeCrusader · 80d ago
Oh that's cool - I had no idea it was used in UK schools, thanks for sharing this!
gortok · 80d ago
As someone who is colorblind (Deuteranopia), the first level asks to swap the green and brown frog. With the hues used, I can’t tell the difference between the two frogs.
Jtsummers · 80d ago
The frogs only move in the direction they face. Move them so that all the frogs facing right are on the right, and facing left are on the left.
CodeCrusader · 80d ago
Good call! The facing direction was meant to help, but I can see how the colors could still be tricky. I’ll look into making it clearer — appreciate the feedback!
CodeCrusader · 80d ago
Hey everyone, I’m the author—really appreciate all the feedback here. If you want to follow along with what I’m working on, I’m over on Twitter: https://x.com/rv_labs. Thanks again!
0cf8612b2e1e · 80d ago
Well, I burst out laughing when I jumped on the transformer lily pad. I assumed there was a trick, but not that.

Quite cute diversion.

jcjmcclean · 80d ago
Really enjoyed that! I was surprised by how fun it was considering how simple it seems. Definitely would love it to last longer.
CodeCrusader · 80d ago
Thanks! Might play with more levels if people keep enjoying it.
stanac · 80d ago
Really fun. Third level was harder than fourth.
CodeCrusader · 80d ago
Ha, you're not the first to say that about level 3! I think I accidentally made the difficulty curve a bit wonky there. Glad you had fun with it!
thaumasiotes · 80d ago
I'm curious about the difficulty curve. As long as the puzzles take the form "group of left-facing frogs - empty pad - group of right-facing frogs", they'll all have exactly the same solution. If you can do level 2, you can do level 2222 without needing to come up with any new ideas.

This kind of blocks the notion of a "difficulty curve" - it's just a flat line.

Level 4 is different, but I'm guessing the reason people say it's easier is that the frogs on the left never need to interact in any way with the frogs on the right. You can just march your left-frogs onto the transformer, see them turn around, and march them back to their ultimate destination, then repeat the process on the right.

I don't think there's any solution that would allow a frog to jump over the transformer, so you're essentially required to do this - all frogs must make their way to the transformer, transform, and go back home - although you can make it look more or less complex. This essentially gives you two copies of the "level 3 and below" puzzle, one on the left of the transformer and the other on the right.

KPGv2 · 80d ago
Really fun game. I was happy when I thought I screwed up the final level only to realize my screwup was the solution.
CodeCrusader · 80d ago
Glad you enjoyed the mind-bend
lozzo · 80d ago
I am so pleased I stumbled on this little game by chance. Really lovely. Well done. Keep it up
CodeCrusader · 80d ago
Thanks! Really made my day to hear you found it by chance and enjoyed it.
necovek · 80d ago
On the last level, getting all the frogs converted to one colour and lined up on one side did not recognize the level as complete.

Did I mess the direction or is this by design or is it an omission?

fl1pper · 79d ago
Liked it. Especially level 4 with frog mutation ;) Definitely bookmarking it. Will there be any updates to add new levels?
camcil · 80d ago
Claude Sonnet 3.7 has a hell of a time with this.
Jtsummers · 80d ago
How so? This is an old puzzle with lots of versions online, I'm surprised it'd be struggling with it (except for the twist that I'll leave out for one of the levels).
parliament32 · 80d ago
Why does it surprise you that a text generator isn't competent at spatial reasoning?
Jtsummers · 80d ago
It depends on how it's explained. The puzzle, depending on phrasing, is not too dissimilar from other movement puzzles like river crossing puzzles. What I'm curious about is how it was explained to the LLM and how an answer was expected in response. You can probably even find text descriptions of solutions online so if you use the right keywords it would likely give a correct solution even if your puzzle description was wonky.
CodeCrusader · 80d ago
Hah! Makes me feel better about struggling with level 3.
Y_Y · 80d ago
Fun, but only lasts about two minutes. Could be interesting in 2d or with some other gimmicks added.
freehorse · 80d ago
I think it lasting 2 minutes is actually an asset. Even though a 2d version etc would be quite interesting, it is great to try such little nice things and then move on to one's day, not everything in the internet has to take that long. And unless one wants to show ads or sth, there is no incentive to actually make it longer anyway.
sse · 80d ago
In 2D, it would become sokoban, wouldn't it?
thaumasiotes · 80d ago
No? Sokoban involves a single agent pushing blocks around a grid. No block can ever move without being pushed, and nothing can ever cross anything else.

In this puzzle, the only way for anything to move is independently, and everything is free to cross anything else.

singleshot_ · 80d ago
If this was two dimensional, it would be the game Hi-Q, more or less.
thaumasiotes · 80d ago
Solitaire removes the pegs that are jumped over. If this was two-dimensional, it would be Chinese Checkers.
dez11de · 80d ago
Stuck on level 8. Any pointers?
themjt · 80d ago
You had me for a second there lol
Sontho · 79d ago
Loved it, it's so simple and difficult at the same time. Good job.
H3X_K1TT3N · 80d ago
I clicked the frogs, but nothing happened. Am I doing it wrong or is it broken?
H3X_K1TT3N · 80d ago
wait, I reopened the link in a new tab and it's suddenly working; not sure what's up with that.
H3X_K1TT3N · 80d ago
welp, that was short, but neat
CodeCrusader · 80d ago
Short and sweet was the goal. Cheers for giving it a go.
owjofwjeofm · 77d ago
I would like being able to press z to undo a move
Fredkin · 80d ago
I get SSL_ERROR_RX_RECORD_TOO_LONG when trying to visit this site.
johnthescott · 80d ago
cool. an interactive version of the knights and knaves book by ray Smullyan would be cool, as well. nice work.
dgellow · 80d ago
That was a very cute puzzle, well done
CodeCrusader · 80d ago
Glad you found it cute. Was aiming for that mix of simple looks but tricky solution.
thenthenthen · 80d ago
I possess no logic
kater006 · 80d ago
Moar
frostirosti · 80d ago
paging 2000s Bethesda puzzles
gus_massa · 83d ago
I don't see any frog.
CodeCrusader · 83d ago
My bad, I messed up with WebP images optimization, should be working now, thanks for letting me know!
gus_massa · 82d ago
It's fixed now. Nice twist at the 4th level.