Comments on: Algorithm Problem – Binary Tree to List http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/ Sat, 08 Aug 2009 01:10:38 +0000 http://wordpress.com/ hourly 1 By: kristian lejao http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-1596 kristian lejao Mon, 20 Apr 2009 01:37:00 +0000 http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-1596 Oops! Nevermind Oops! Nevermind

]]> By: kristian lejao http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-1594 kristian lejao Fri, 20 Feb 2009 17:09:06 +0000 http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-1594 I think I got a solution from this using Python.. :P def to_list(tree): if tree is None: return None else: return [tree.key, tree.left, tree.right] I think I got a solution from this using Python.. :P

def to_list(tree):
if tree is None:
return None
else:
return [tree.key, tree.left, tree.right]

]]> By: ytik ytkyt http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-1582 ytik ytkyt Fri, 08 Aug 2008 11:35:35 +0000 http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-1582 wt? wt?

]]> By: amod http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-1550 amod Thu, 01 May 2008 03:38:16 +0000 http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-1550 How about the following (based on inorder walk). // explore returns a circular linked list // at each level. explore(node): lnode = explore(node.left) lnode.left.right = node node.left = lnode.left rnode = explore(node.right) rnode.left.right = lnode lnode.left = rnode.left rnode.left = node node.right = rnode return lnode this runs in O(n) and works for a perfectly balanced tree. For an imbalanced tree we'll need to create self loops if a left/right child is missing. I didn't test this thoroughly but it seems to work. How about the following (based on inorder walk).

// explore returns a circular linked list // at each level.
explore(node):
lnode = explore(node.left)
lnode.left.right = node
node.left = lnode.left
rnode = explore(node.right)
rnode.left.right = lnode
lnode.left = rnode.left
rnode.left = node
node.right = rnode
return lnode

this runs in O(n) and works for a perfectly balanced tree. For an imbalanced tree we’ll need to create self loops if a left/right child is missing. I didn’t test this thoroughly but it seems to work.

]]> By: Sunil Jagadish http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-932 Sunil Jagadish Thu, 14 Jun 2007 16:01:24 +0000 http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-932 The very order 1, 2, 3, 4, 5 indicates that what you require is in in-order. Though I haven't thought strongly about its exact implmentation, I think this should be possible. The very order 1, 2, 3, 4, 5 indicates that what you require is in in-order. Though I haven’t thought strongly about its exact implmentation, I think this should be possible.

]]> By: Binary Tree to List- Solutions.. « the madcap laughs….. http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-96 Binary Tree to List- Solutions.. « the madcap laughs….. Tue, 03 Apr 2007 05:35:34 +0000 http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-96 [...] on April 3rd, 2007. Zaki has presented an interesting perspective at the original problem [...] [...] on April 3rd, 2007. Zaki has presented an interesting perspective at the original problem [...]

]]> By: Nirmal http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-95 Nirmal Tue, 03 Apr 2007 05:09:39 +0000 http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-95 yes, i did have a graph theory course at college, however i've not tried many algorithms with graph theory concepts... an avl and the red-black would be below O(n) i agree... yes, i did have a graph theory course at college, however i’ve not tried many algorithms with graph theory concepts…
an avl and the red-black would be below O(n) i agree…

]]> By: zakimirza http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-92 zakimirza Sun, 01 Apr 2007 20:02:49 +0000 http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-92 that asks for another quiz btw :) given two differnt trees, convert between them OPTIMALLY. have you worked on graph drawing? this kind of problems arise there sparingly. For example, give a very dense graph, you might want to visualize it in different ways etc. that asks for another quiz btw :) given two differnt trees, convert between them OPTIMALLY. have you worked on graph drawing? this kind of problems arise there sparingly. For example, give a very dense graph, you might want to visualize it in different ways etc.

]]> By: zakimirza http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-91 zakimirza Sun, 01 Apr 2007 20:00:11 +0000 http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-91 Thank you for appriciating my blog. I think the efficiency in the worst case can be when the three is totally balanced. it would be fun to see how this bahaves on a AVL or redblack. But its gotta be some factor below n for sure. lets c. Thank you for appriciating my blog. I think the efficiency in the worst case can be when the three is totally balanced. it would be fun to see how this bahaves on a AVL or redblack. But its gotta be some factor below n for sure. lets c.

]]> By: Nirmal http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-88 Nirmal Sun, 01 Apr 2007 04:02:19 +0000 http://nirmalthacker.wordpress.com/2007/03/31/algorithm-problem-binary-tree-to-list/#comment-88 Zaki, interesting technique!.. besides examining the efficiency of your algorithm would be a subject of another post..its really interesting cause i jus realized that given two different binary search trees on a given set of n keys, it is always possible to transform one tree into the other, using only a sequence of O(n) rotations. However since your recursive function digs into the tree... and now i wanna experiment this with several trees...and pulls out balance trees, converts them into a list, im wondering if the efficiency would be decent. Nevertheless , its a super perspective. Your blog is sure good! Great post here! http://zakimirza.wordpress.com/2007/03/28/about-quizes-and-blog/ Zaki, interesting technique!.. besides examining the efficiency of your algorithm would be a subject of another post..its really interesting cause i jus realized that given two different binary search trees on a given set of n keys, it is always possible to transform one tree into the other, using only a sequence of O(n) rotations. However since your recursive function digs into the tree… and now i wanna experiment this with several trees…and pulls out balance trees, converts them into a list, im wondering if the efficiency would be decent.
Nevertheless , its a super perspective.

Your blog is sure good! Great post here! http://zakimirza.wordpress.com/2007/03/28/about-quizes-and-blog/

]]>