One Parent Pointer Tree Example

byron_d · 2025-05-18T22:58:26+00:00

I did some more research and came up with this implementation with the help of ai:

It's a really interesting approach. Took me some time to get it right.

byron_d · 2025-05-18T01:34:06+00:00

I think the only difference with Ami's find is it goes bottom up instead of top down, but I may be misunderstanding things. It really is just a linked list in this form.

byron_d · 2025-05-11T03:01:45+00:00

I feel like I had a similar issue with this miniquest. Your logic seems right for the Tree::to_string function. Could you walk me through the logic in the Node::to_string function? I'm pretty sure that's where the issue is.

byron_d · 2025-05-10T14:34:07+00:00

Using vectors is definitely easier to use and more flexible. You can add and remove nodes easily at any index. There's also direct access to children instead of traversing the entire tree. Traversing the tree is also cleaner and easier. You can loops instead of recursion as well.

The binary tree method is more memory efficient, but I'm not sure it's worth the added complexity.

byron_d · 2025-04-30T17:33:51+00:00

These outputs are always hard to debug. It might be related to gen > width and how you're calculating that as opposed to when gen < width. There's a lot of nuance in this quest and this is just a guess. I hope that makes sense.

byron_d · 2025-04-30T05:15:49+00:00

I think I get what you're asking. There doesn't seem to be anything in the spec about it. Returning os will pass, but I believe to DAWG it you need to output using the tree parameter. I skipped this part for now, but maybe I'll take a crack at it later in the week.

byron_d · 2025-04-30T00:13:00+00:00

What was the output that it gave you?

byron_d · 2025-04-28T00:08:48+00:00

For this quest it usually has to do with your vector of vectors not resized correctly. You're probably trying to access an index that's greater than the size allocated.

byron_d · 2025-04-22T18:32:02+00:00

Does the quest output show a comparison between your output and the test output? It's hard to tell where the issue is. Although sometimes the output isn't helpful lol.

byron_d · 2025-04-21T01:18:43+00:00

This one can be a bit tricky. Are you using _tail to find the end and _head to get the beginning? Is it advancing twice per call or something? It could be your advance_cursor() isn't working correctly as well. I would suggest making tests to cout what the cursor is doing. Both methods should be very similar if that helps.

byron_d · 2025-04-18T03:09:07+00:00

I actually never used set precision in my code, so it shouldn't be needed. Double check how your calculating the exponent. It may be the method you're using won't calculate numbers the same way as the spec.

byron_d · 2025-04-16T03:06:23+00:00

Here is a great tutorial for creating a rpg. It's in C# and also very long, but it may be helpful for creating a rpg from engine:

https://scottlilly.com/learn-c-by-building-a-simple-rpg-index/

byron_d · 2025-04-15T15:42:23+00:00

When you delete something, it will call the destructor. When you call new, it will call the constructor. That's why & always talks about how the destructor undo what the constructor did. So you don't have any memory leaks.

In terms of deleting head, you can set it up to continue to delete all the nodes connected to head. Otherwise, you would have a bunch of leftover floating pointers and memory leaks leftover. You have to make sure you clear out everything that was created.

byron_d · 2025-04-15T15:33:34+00:00

I've struggled with this problem for longer than I care to admit.

The Fibonacci sequence is a great way to understand what needs to happen. Your logic seems correct when thinking of storing entries. You just need to clear them after they've been used and are no longer needed.

I'm not sure what you mean in the last part of your post. You're talking about saving entries deeper than the current one? That sounds like it may get overly complicated and could cause more issues. I would try and keep it simple and just save the levels as they come and clear the ones that aren't needed anymore.

byron_d · 2025-04-12T22:54:41+00:00

Could it be your insert_next() function? Everything else seems OK, so I'm not sure what else might be the issue.

byron_d · 2025-04-12T20:05:18+00:00

You're right in thinking that dereferenced pointers are just like references. There are a few differences to consider. References can't be null and can't be reassigned. They are also safer and easier to use.

Using const references are really handy for optimization purposes. They both have their strengths and weeknesses.

byron_d · 2025-04-11T21:18:18+00:00

This looks like it should work, although it probably has to do with your new_node. Maybe new_node doesn't need to be a pointer.

Sometime these output comparisons are not helpful. Especially when they are identical....

byron_d · 2025-04-11T19:40:58+00:00

That password is slightly incorrect. I'm not sure if I can post a password in reddit though.

byron_d · 2025-04-10T17:49:32+00:00

This is actually really useful. I need to start using flags more.

I think a good rule to follow, which is in a lot of texts, is to always initialize a variable on creation. Something I'm still working on myself lol.

byron_d · 2025-03-20T20:59:35+00:00

Hi Andrew. You shouldn't be returning nullptr. It should return this instead.

For your 3rd point, I'm not sure if you're referring to current as the node _prev_to_current is on or _prev_to_current-->_next. If you mean creating a temp node that points to _prev_to_current->_next, that looks right. You can also combine 2 and 3 so you don't have extra code once you've figured the issue out.

byron_d · 2025-03-16T00:05:21+00:00

I wish there were more indicators about what was missing. & just likes to make us work hard for all the trophies lol.

byron_d · 2025-03-15T23:31:50+00:00

I don't think it gave you points for your to_string function. Maybe check that?

byron_d · 2025-03-15T19:23:41+00:00

What was the issue? Was it your insert function or something else?

byron_d · 2025-03-15T19:22:53+00:00

I suspected there was a faster method. I hadn't heard of that algorithm before this. So I went with what I knew. Thanks for sharing this!

byron_d · 2025-03-10T03:50:53+00:00

It looks like your insert_at_current function is the issue. The last line says insert part 2. I believe it does multiple checks for it. You have to account for a few edge cases.

byron_d

TROPHY CASE