Any good algorithm to balanced a strict binary tree for a ordered set

Hi,
I have created a syntax tree of a binary operator that is associative but not commutative. The resultant is a unbalanced strict binary tree.
I have tried using AVL tree as well as a heap. But they will occasionally destruct the non-commutative property of the syntax tree.
Is there any efficient algorithm that I can used to balance this tree?
Thank you.

Is linear time good enough?
1. Traverse your tree to build a list.
2. Recursively turn the list into a tree. Pseudocode for this step: fun listToTree( [a] ) = Leaf(a)
| listToTree( xs ) = Node( listToTree(firstHalf(xs)), listToTree(secondHalf(xs)) );

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Binary tree for parsing algebraic expressions

hi all
i have a project to do.. i need to read in an algebraic expression, parse it and form a binary tree. later use that tree to evaluate the expressions when the actual value for those variables are passed..
can anyone tell me how to go about doing this.
im a beginner in java..
tks

first of, your going to need three stacks. The implementation of a stack in JAVA is something that's easy to find, do a forum search. Your going to need a Binary Node as well. One stack will hold the operator elements of your algebraic expression, another will hold the numeric values, and the final will hold your binary nodes:
expression: 4 + 6 - (6 * 9)
now there are some rules that should be followed. Whenever a closing parenthesis is encountered ")", pop an operator, pop two numbers, and create the corresponding binary node.
order of operations:
push 4 onto numberStack
push + onto operatorStack
push 6 onto numberStack
push - onto operatorStack
push ( onto operator Stack
push 6 onto numberStack
push * onto operatorStack
push 9 onto numberStack
")" encountered
Now, your stacks look something like this:
operatorStack: [ +, -, (, *, ) ]
numberStack: [ 4, 6, 6, 9 ]
pop 9 and 6 from numberStack, pop * from operatorStack
build a binaryNode using these three elements
push this node onto the binaryNodeStack
I.E. using the expression above:
/ \ is the resulting binary node once the ")" is received.
6 9
etc.. there are some rules regarding when to pop and build binary nodes, it's been a while since i did this assignment and frankly my brain hurts, hope this gets you started, good luck.

Any Good FREE FCP Video Tutorials Like LiveTypeCentral Do For LT ?

Recently my attention was drawn to some very good FREE video tutorials provided by LiveTypeCentral:-
http://www.livetypecentral.com/cgi-bin/livetypecentral.cgi/tutorials.html
I was wondering if there are any similar free ones covering FCE/FCP or the other FCS apps?
I don't need them of course ....... they are just for friends! (If you believe that you'll believe anything).
Incidentally I have done a search and had a look at the Creative Cow ones, but they tend to be on somewhat random esoteric subjects.
I am looking for something that starts with the basics of the apps.
Message was edited by: Ian R. Brown

Sorry, I didn't make it clear.
I mainly wanted freely available tutorials that I could direct others to on the FCE and other forums. Frequently newcomers don't know where to start, and I don't have time to write a new manual, so it is very efficacious to be able to point them to a site with free tutorials.
That LiveType source I quoted is excellent. So now, basically all I am looking for is a similar one for Soundtrack and FCE/FCP.
The first one you linked is probably fine except for the download time which would probably have taken several hours per tutorial, which is going to put off many newcomers looking for a quick-fix.
I must admit I also like looking at tutorials (I never used to!) because every one of them has a different angle and it's surprising what you can pick up, that you have missed in others.

Any good place to get native extensions? (looking for an ok/cancel modal dialog myself)

Hi all,
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Thanks very much, this is right up the alley I wanted! I will try this and report back!
edit:
Geez you can't even get Xcode 4.2 without Lion. I had to update my system just to get Xcode 4.2 so unfortunately testing will need to wait until tomorrow..

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@Sarchet: See this user tip by Karsten Schlüter for all the options of making a video DVD - you might give the free "Burrn" a try:
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Hello,
Given a list of figures:
1899.09
345.55
300.00
130.05
90023.00
45.90
120.50
8831781.56
505.00
45.55
Then the program need to find all the possible addition of figures that will able to produce a answer, for example, 550.55
Then the possible additions are:
300.00 + 120.50 + 130.05 = 550.55
505.00 + 45.55 = 550.55
any good algorithm or sample code?
Thanks for any help.

A general knapsack problem solver is overkill here if one just wants to find a combination that fits 'perfectly'. If the list of numbers is small (< 100), a simple exhaustive search will do fine (read: it's fast). Have a look at the following sample class that solves this particular problem. Note that the set of numbers is a set of integer numbers, because floating point numbers don't add up well; in particular large and small numbers added will result in very inaccurate sums.
kind regards,
public class Comb {
     private int   u; // index of used numbers sofar
     private int   s; // the sum to be found
     private int[] c; // the candidate numbers
        // given a set of numbers and a sum, instantiate a solver
     public Comb(int[] c, int s) {
          this.c= c;
          this.s= s;
          this.u= c.length;
        // yes, swap two elements in array c
     private void swap(int i, int j) {
          int t= c;
          c[i] = c[j];
          c[j] = t;
// use the number at index i as a try
     private void use(int i) {
          swap(i, --u);
// unuse the number at index i
     private void unuse(int i) {
          swap(i, u++);
// proccess (e.g. print) a current solution
// note that this method could throw an exception if
// just one solution is needed.
     private void solution() {
          for (int i= u; i < c.length; ++i) {
               System.out.print(c[i]);
               if (i < c.length-1)
                    System.out.print("+");
          System.out.println("="+s);
// find all solutions to this problem
     public void find(int t) {
          if (t == 0) // ready?
               solution();
          else if (t > 0) // still more to do?
               for (int i= 0; i < u; ++i) {
                    use(i);
                    find(t-c);
                    unuse(i);
// solve the example problem ... == 11
     public static void main(String[] args) {
          int c[]= { 5, 3, 6, 8 };
          int s = 11;
          new Comb(c, s).find(s);

Are these any good TP-Link TL-WR1043ND

Hi,
Just looking to replace the HH3 as I find my speed slows right down until rebooted. Once I have done this it works great for a few days and then slows right down again. I am only rebooting the HH3 and the modem stays on so makes me think it is the unit. Just wondering what experiences other people have out there and wheather the above box would be any good to replace the HH3 with.
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walkerx wrote:
Nice link that you can't view unless you connected via BT Internet
I'm browsing from another network at moment and you get blocked from view it
Sorry - You must be connected to BT Broadband or the BT network to use this website
My website is running on a private server and is restricted to BT Broadband and those connected to the BT network, as its intended as a help site for forum members.
If you access via BT Wifi, you should be able to view it as well, although sometimes my reverse DNS lookup fails on some of these subnets, but I am keeping a watch to see which ones are failing.
Unfortunately, opening up the website to the whole world, results in an exponential increase in bandwidth due to linking by search engines, attacks by hackers and other issues as well.
There are some useful help pages here, for BT Broadband customers only, on my personal website.
BT Broadband customers - help with broadband, WiFi, networking, e-mail and phones.

Any good dot matrix printers for macbook pro w/ osx tiger

anybody got any good advice on a compatible dot matrix printer for a macbook pro running osx 10.4 tiger. want to print about 30-2 part time cards per week with excel or filemaker pro 9.0 and having a hard time finding current info on compatibility. want a reasonably priced printer which is useful without a whole lot of technical wizardry involved!

Check out the Okidatas too...
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Hi,
I'm thinking about getting the VMware Fusion to run windows on my mac today, but just wanted to know does anyone have/had it on their laptop and was it indeed any good? I tried searching on the website for it but can't find it to see how much it is in UK Pounds only in USA dollars.
Thanks

Just to add my two cents as it were, I've been using VMWare Fusion for at least a year now and the only problems that I've had is it not running some of my more graphics heavy games.
For using Office and Messenger though it work perfectly. There's no slowdown when using it. You can create a virtual machine for pretty much any OS as long as you have the install files.
Also, if you have a Boot Camp partition you can load that up as a virtual machine so you don't have to install a separate one. Although, I have a Boot Camp partition set up and I've also got a VM of the same Windows that is only running Office and a few other programs so that I can easily check compatibility.
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Help loading a binary tree from file

Hi all,
So I am working on making a 20 question game using a binary tree. I have set it up so each time the user plays, if the computer cannot guess what they are thinking of, they tell the computer and it saves it. I am saving the tree in a text file recursively, in a format that looks something like this:
Do you use it outside?
a shovel
[null]
[null]
is it round?
a ball
[null]
[null]
a TV
[null]
[null]
The problem is now, I am having a very hard time rebuilding the tree when the user restarts the game. As you can see, the "{" indicates the beginning of a path and the "}" is the end. Can someone suggest a nice way to load this back up into my data structure? Thanks!!

Cross-post here: [http://www.java-forums.org/java-2d/14237-help-loading-binary-tree-file.html]
Recommended looking into XML

How to extend breadth first Search for Binary Tree to any kind of Tree??

Dear Friends,
I am thinking a problem, How to extend breadth first Search for Binary Tree to any kind of Tree?? ie each node has more than 2 leaves such as 1, 2,3,4 or any,
I have following code to successfully apply for breadth first Search in Binary Tree as follows,
package a.border;
import java.util.ArrayList;
import java.util.LinkedList;
public class Tree
    int root;
    Tree left;
    Tree right;
    static ArrayList<Integer> list = new ArrayList<Integer>();
    static ArrayList<Tree> treeList = new ArrayList<Tree>();
    private static LinkedList<Tree> queue = new LinkedList<Tree>();
     * @param root root value
     * @param left left node
     * @param right right node
    public Tree(int root, Tree left, Tree right)
        this.root = root;
        this.left = left;
        this.right = right;
    /** Creates a new instance of Tree
     * You really should know what this does...
     * @param root
    public Tree(int root)
        this.root = root;
        this.left = null;
        this.right = null;
     * Simply runs a basic left then right traversal.
    public void basicTraversal()
        //Check if we can go left
        if (left != null)
            left.basicTraversal();
        //Add the root
        list.add(root);
        //Check if we can go right
        if (right != null)
            right.basicTraversal();
    public ArrayList<Integer> getBreadthTraversal(ArrayList<Integer> list)
        //Add the root to the arraylist, we know it is always the first entry.
        list.add(root);
        //Basically we add the first set of nodes into the queue for
        //traversing.
        //Query if left exists
        if (left != null)
            //Then add the node into the tree for traversing later
            queue.add(left);
        //Same for right
        if (right != null)
            queue.add(right);
        //Then we call the traverse method to do the rest of the work
        return traverse(list);
    private ArrayList<Integer> traverse(ArrayList<Integer> list)
        //Keep traversing until we run out of people
        while (!queue.isEmpty())
            Tree p = queue.remove();
            //Check if it has any subnodes
            if (p.left != null)
                //Add the subnode to the back of the queue
                queue.add(p.left);
            //Same for left
            if (p.right != null)
                //Same here, no queue jumping!
                queue.add(p.right);
            //Append to the ArrayList
            list.add(p.root);
        //And return
        return list;
     * Makes a tree and runs some operations
     * @param args
    public static void main(String[] args)
         *                             4
         *          t =           2       6
         *                      1   3    5   7
        Tree leaf6 = new Tree(1);
        Tree leaf7 = new Tree(3);
        Tree leaf8 = new Tree(5);
        Tree leaf9 = new Tree(7);
        Tree t4 = new Tree(2, leaf6, leaf7);
        Tree t5 = new Tree(6, leaf8, leaf9);
        Tree t = new Tree(4, t4, t5);
        t.basicTraversal();
        System.out.println("Here is basicTraversal ="+list.toString());
        list.clear();
        t.getBreadthTraversal(list);
        System.out.println("getBreadthTraversal= " +list.toString());
        list.clear();
    }Can Guru help how to update to any kind of tree??
here this code is for the tree like:
         *                             4
         *          t =           2       6
         *                      1   3    5   7
         */But i hope the new code can handle tree like:
         *                             4
         *                           /   | \
         *                          /     |   \
         *          t =            2     8   6
         *                        / | \    |    /| \
         *                      1 11 3 9   5 10 7
         */Thanks

sunnymanman wrote:
Dear Friends,
I am thinking a problem, How to extend breadth first Search for Binary Tree to any kind of Tree?? ...The answer is interfaces.
What do all trees have in common? And what do all nodes in trees have in common?
At least these things:
interface Tree<T> {
    Node<T> getRoot();
interface Node<T> {
    T getData();
    List<Node<T>> getChildren();
}Now write concrete classes implementing these interfaces. Let's start with a binary tree (nodes should have comparable items) and an n-tree:
class BinaryTree<T extends Comparable<T>> implements Tree<T> {
    protected BTNode<T> root;
    public Node<T> getRoot() {
        return root;
class BTNode<T> implements Node<T> {
    private T data;
    private Node<T> left, right;
    public List<Node<T>> getChildren() {
        List<Node<T>> children = new ArrayList<Node<T>>();
        children.add(left);
        children.add(right);
        return children;
    public T getData() {
        return data;
class NTree<T> implements Tree<T> {
    private NTNode<T> root;
    public Node<T> getRoot() {
        return root;
class NTNode<T> implements Node<T> {
    private T data;
    private List<Node<T>> children;
    public List<Node<T>> getChildren() {
        return children;
    public T getData() {
        return data;
}Now with these classes, you can wite a more generic traversal class. Of course, every traversal class (breath first, depth first) will also have something in common: they return a "path" of nodes (if the 'goal' node/data is found). So, you can write an interface like this:
interface Traverser<T> {
    List<Node<T>> traverse(T goal, Tree<T> tree);
}And finally write an implementation for it:
class BreathFirst<T> implements Traverser<T> {
    public List<Node<T>> traverse(T goal, Tree<T> tree) {
        Node<T> start = tree.getRoot();
        List<Node<T>> children = start.getChildren();
        // your algorithm here
        return null; // return your traversal
}... which can be used to traverse any tree! Here's a small demo of how to use it:
public class Test {
    public static void main(String[] args) {
        Tree<Integer> binTree = new BinaryTree<Integer>();
        // populate your binTree
        Tree<Integer> nTree = new NTree<Integer>();
        // populate your nTree
        Traverser<Integer> bfTraverser = new BreathFirst<Integer>();
        // Look for integer 6 in binTree
        System.out.println("bTree bfTraversal -> "+bfTraverser.traverse(6, binTree));
        // Look for integer 6 in nTree
        System.out.println("bTree bfTraversal -> "+bfTraverser.traverse(6, nTree));
}Good luck!

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Just testing out my new Intel Mac Mini's faxing capabilities. It seems that the faxing status details when I view the fax monitor isn't quite as accurate as I need. For example, after I mistakenly tried to send a fax out via my printer/fax machine, I cancelled it before it finished dialing, but still the status of it showed that it was "Finished".
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is the i phone any good for those with essential tremour

Hi auchenshugglegranny,
Welcome to the Support Communities!
The iPhone has a number of accessibility features that may be helpful to you, including Siri, which will accept voice commands. The article below will provide an overview for you.
Apple - Accessibility
http://www.apple.com/accessibility/
Below is a list of features included in the iPhone User Guide:
Accessibility features - iPhone
http://help.apple.com/iphone/7/#/iph3e2e4367
VoiceOver
Support for braille displays
Siri
Zoom
Invert Colors
Speak Selection
Speak Auto-text
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Subtitles and closed captions
LED Flash for Alerts
Mono audio and balance
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Phone noise cancellation
Guided Access
Switch Control
AssistiveTouch
Widescreen keyboards
Turn on accessibility features. Go to Settings > General > Accessibility, or use the Accessibility Shortcut. See Accessibility Shortcut.
Use iTunes to configure accessibility. You can choose some accessibility options in iTunes on your computer. Connect iPhone to your computer and select iPhone in the iTunes device list. Click Summary, then click Configure Accessibility at the bottom of the Summary screen.
Hope this information helps ...
Happy Holidays!
Judy

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thanks in advance,
Anil

Here are some sites I have been directed to:
http://graphdrawing.org/
Graph Drawing: Algorithms for the Visualization of Graphs (Paperback)
by Ioannis G. Tollis, Giuseppe Di Battista, Peter Eades, Roberto Tamassia

Any good faq sites for ppl new to solaris?

Hi, just want to know if there are any good sites that teach
the basics on solaris and samba

Hi,
You try this URL:
http://docs.sun.com
Thanks.
revert back.
regards,
Senthilkumar
SUN - DTS

Any good algorithm to balanced a strict binary tree for a ordered set

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