Not to put words into Hossein's mouth...but I'm going to. It sounds like he's looking for a data structure that represents a plain old tree - no ordering, just the parent/child relationships. A family tree (rooted at a single person) would be a good example.

That's exactly what I meant! But my concrete problem is some hierarchy in Civil Engineering.

I think this was discussed before on this mailing list, The (obvious) solution was to use a graph, and if necessary, add code that constrains it to satisfy the tree properties.

Apologies if I'm wrong. :P Not only you weren't wrong, but also you were

And how can I find the related emails? Can you remember the topic for those? perfectly right! Thanks, --Hossein __________________________________ Do you Yahoo!? Yahoo! Calendar - Free online calendar with sync to Outlook(TM). http://calendar.yahoo.com

I went back and looked, and in Kasper Peeters' response to your original email, he pointed to a generic n-ary tree (imho a good solution):

http://www.damtp.cam.ac.uk/user/kp229/tree/#structure Thanks a lot. I think you have given me the right stuff.

His email is here:

http://article.gmane.org/gmane.comp.lib.boost.user/3564/match=+kasper+peeter... You made to doubt in my memory, as I don't remember getting such an email.

I'd agree with some of the other responses, though...the basic, five-line solution is extremely simple, and it works. If you need extra operations like tree traversals or search, they may depend on your specific problem enough that you'd benefit from a custom-tailored solution.

Yes, may be. Thanks again, --Hossein __________________________________ Do you Yahoo!? Yahoo! Calendar - Free online calendar with sync to Outlook(TM). http://calendar.yahoo.com

From: "Hossein Haeri"

In fact, the tree I want to represent is just a hierarchy. The only fact that I know about this hierarchy is the parent/child relationship.

This still makes it hard to come up with a solution for it, because you don't say what operations are needed on the tree, or how many children there are - although you said _binary_ search tree, but as others have pointed out, with the tree being unordered, it's no longer a search tree, so one may wonder if the binary part is correct, too. Given your current description of what you want, here's one that satisfies it: template<class T> struct tree_node { T data; tree_node *left; tree_node *right; }; This isn't intended to be sarcastic, but rather to point out that so far you've provided way too little information about what you want to do with the tree, to be able to give a meaningful reply (other than the links to present libraries). Regards, Terje

From: "Hossein Haeri"

...

This still makes it hard to come up with a solution for it, because you don't say what operations are needed on the tree, or how many children there are - although you said _binary_ search tree, but as others have pointed out, with the tree being unordered, it's no longer a search tree, so one may wonder if the binary part is correct, too.

I don't know how to get the group to forgive me. Doesn't the group receive all of my answers, while I myself do? I think it was more than a couple of days ago that I did apologize because of that silly mistake. I'm really astonished seeing people still trying to answer my original message, while I have sent several corrections on it. I redo it one time more: EXCUSE ME BECAUSE OF SPEAKING SO CARELESSLY. The container I need is not a binary tree at all.

Yes, I read your recent posting where you said it was to model a hierarchy, of parent/child. Yet, that doesn't contradict a binary tree structure, depending on the number of children, so I thought that part might still be correct. Anyway, I understand you now may have found something you can use. Regards, Terje