A red-black tree is a particular implementation of a self-balancing binary search tree, and today it seems to be the most popular choice of implementation. Binary search trees are used to implement finite maps, where you store a set of keys with associated values. You can also implement sets by only using the keys and … Read more
Using homebrew: brew install tree Using macports: sudo port install tree Using the source: Follow these directions. (Caveat; you should use the flags/etc. that make sense.) <rant>All systems should come with tree; I use it a lot. And we can post directory structures as text, not pics.</rant>
You can use a TreeMap data structure. TreeMap is implemented as a red black tree, which is a self-balancing binary search tree.
I have 3 possible answers. The sql fiddle for your question is here: http://sqlfiddle.com/#!3/7c7a0/3/0 The sql fiddle for my answer is here: http://sqlfiddle.com/#!3/5d257/1 Warnings: Query Analyzer is not enough – I notice a number of answers were rejected because their query plans are more expensive than the original query. The Analyzer is only guide. Depending … Read more
If I were to do this, I’d probably do something like the following: For each leaf node, compute the concatenation of 0 and the hash of the node data. For each internal node, compute the concatenation of 1 and the hash of any local data (NB: may not be applicable) and the hash of the … Read more
We had a similar problem in the past. And found a nice solution: Give each image an unique guid. Create a database record for each image containing the name, location, guid and possible location of sub images (thumbnails, reducedsize, etc.). Use the first (one or two) characters of the guid to determine the toplevel folder. … Read more
There are no differences between the words Node and Vertex. Even in some books that explain graph theory and graph algorithms they name it as: Vertex denoted by v, and sometimes it’s called nodes also There are no major nor minor differences between them. This is mentioned in the book: Data structure and Algorithms with … Read more
Here are some libraries that you may find helpful: arboreal.js, a “micro-library for traversing and manipulating tree-like data structures” in node.js and the browser. buckets, a “complete, fully tested and documented data structure library” that includes BSTs, a heap, and a bunch of other goodies.
If you’re implementing a tree structure in C# (or Java, or many other languages) you’d use references instead of pointers. NB. references in C++ are not the same as these references. The usage is similar to pointers for the most part, but there are advantages like garbage collection. class TreeNode { private TreeNode parent, firstChild, … Read more
oke this is how i solved it: $arr = array( array(‘id’=>100, ‘parentid’=>0, ‘name’=>’a’), array(‘id’=>101, ‘parentid’=>100, ‘name’=>’a’), array(‘id’=>102, ‘parentid’=>101, ‘name’=>’a’), array(‘id’=>103, ‘parentid’=>101, ‘name’=>’a’), ); $new = array(); foreach ($arr as $a){ $new[$a[‘parentid’]][] = $a; } $tree = createTree($new, array($arr[0])); print_r($tree); function createTree(&$list, $parent){ $tree = array(); foreach ($parent as $k=>$l){ if(isset($list[$l[‘id’]])){ $l[‘children’] = createTree($list, $list[$l[‘id’]]); } … Read more