675 lines
		
	
	
		
			19 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			675 lines
		
	
	
		
			19 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
// Copyright 2011 David Galles, University of San Francisco. All rights reserved.
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//
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// Redistribution and use in source and binary forms, with or without modification, are
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// permitted provided that the following conditions are met:
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//
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// 1. Redistributions of source code must retain the above copyright notice, this list of
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// conditions and the following disclaimer.
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//
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// 2. Redistributions in binary form must reproduce the above copyright notice, this list
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// of conditions and the following disclaimer in the documentation and/or other materials
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// provided with the distribution.
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//
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// THIS SOFTWARE IS PROVIDED BY David Galles ``AS IS'' AND ANY EXPRESS OR IMPLIED
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// WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
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// FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> OR
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// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
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// ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
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// ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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//
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// The views and conclusions contained in the software and documentation are those of the
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// authors and should not be interpreted as representing official policies, either expressed
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// or implied, of the University of San Francisco
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// Constants.
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BST.LINK_COLOR = "#007700";
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BST.HIGHLIGHT_CIRCLE_COLOR = "#007700";
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BST.FOREGROUND_COLOR = "#007700";
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BST.BACKGROUND_COLOR = "#EEFFEE";
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BST.PRINT_COLOR = BST.FOREGROUND_COLOR;
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BST.WIDTH_DELTA  = 50;
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BST.HEIGHT_DELTA = 50;
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BST.STARTING_Y = 50;
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BST.FIRST_PRINT_POS_X  = 50;
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BST.PRINT_VERTICAL_GAP  = 20;
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BST.PRINT_HORIZONTAL_GAP = 50;
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function BST(am, w, h)
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{
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	this.init(am, w, h);
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}
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BST.prototype = new Algorithm();
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BST.prototype.constructor = BST;
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BST.superclass = Algorithm.prototype;
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BST.prototype.init = function(am, w, h)
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{
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	var sc = BST.superclass;
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	this.startingX =  w / 2;
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	this.first_print_pos_y  = h - 2 * BST.PRINT_VERTICAL_GAP;
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	this.print_max  = w - 10;
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	var fn = sc.init;
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	fn.call(this,am);
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	this.addControls();
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	this.nextIndex = 0;
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	this.commands = [];
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	this.cmd("CreateLabel", 0, "", 20, 10, 0);
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	this.nextIndex = 1;
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	this.animationManager.StartNewAnimation(this.commands);
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	this.animationManager.skipForward();
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	this.animationManager.clearHistory();
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}
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BST.prototype.addControls =  function()
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{
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	this.insertField = addControlToAlgorithmBar("Text", "");
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	this.insertField.onkeydown = this.returnSubmit(this.insertField,  this.insertCallback.bind(this), 4);
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	this.insertButton = addControlToAlgorithmBar("Button", "添加");
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	this.insertButton.onclick = this.insertCallback.bind(this);
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	this.deleteField = addControlToAlgorithmBar("Text", "");
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	this.deleteField.onkeydown = this.returnSubmit(this.deleteField,  this.deleteCallback.bind(this), 4);
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	this.deleteButton = addControlToAlgorithmBar("Button", "删除");
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	this.deleteButton.onclick = this.deleteCallback.bind(this);
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	this.findField = addControlToAlgorithmBar("Text", "");
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	this.findField.onkeydown = this.returnSubmit(this.findField,  this.findCallback.bind(this), 4);
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	this.findButton = addControlToAlgorithmBar("Button", "搜索");
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	this.findButton.onclick = this.findCallback.bind(this);
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	this.printButton = addControlToAlgorithmBar("Button", "打印");
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	this.printButton.onclick = this.printCallback.bind(this);
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}
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BST.prototype.reset = function()
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{
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	this.nextIndex = 1;
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	this.treeRoot = null;
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}
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BST.prototype.insertCallback = function(event)
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{
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	var insertedValue = this.insertField.value;
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	// Get text value
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	insertedValue = this.normalizeNumber(insertedValue, 4);
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	if (insertedValue != "")
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	{
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		// set text value
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		this.insertField.value = "";
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		this.implementAction(this.insertElement.bind(this), insertedValue);
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	}
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}
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BST.prototype.deleteCallback = function(event)
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{
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	var deletedValue = this.deleteField.value;
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	if (deletedValue != "")
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	{
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		deletedValue = this.normalizeNumber(deletedValue, 4);
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		this.deleteField.value = "";
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		this.implementAction(this.deleteElement.bind(this),deletedValue);		
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	}
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}
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BST.prototype.printCallback = function(event)
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{
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	this.implementAction(this.printTree.bind(this),"");						
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}
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BST.prototype.printTree = function(unused)
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{
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	this.commands = [];
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	if (this.treeRoot != null)
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	{
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		this.highlightID = this.nextIndex++;
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		var firstLabel = this.nextIndex;
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		this.cmd("CreateHighlightCircle", this.highlightID, BST.HIGHLIGHT_CIRCLE_COLOR, this.treeRoot.x, this.treeRoot.y);
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		this.xPosOfNextLabel = BST.FIRST_PRINT_POS_X;
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		this.yPosOfNextLabel = this.first_print_pos_y;
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		this.printTreeRec(this.treeRoot);
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		this.cmd("Delete",  this.highlightID);
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		this.cmd("Step")
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		for (var i = firstLabel; i < this.nextIndex; i++)
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		{
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			this.cmd("Delete", i);
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		}
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		this.nextIndex = this.highlightID;  /// Reuse objects.  Not necessary.
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	}
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	return this.commands;
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}
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BST.prototype.printTreeRec = function(tree)
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{
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	this.cmd("Step");
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	if (tree.left != null)
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	{
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		this.cmd("Move", this.highlightID, tree.left.x, tree.left.y);
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		this.printTreeRec(tree.left);
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		this.cmd("Move", this.highlightID, tree.x, tree.y);				
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		this.cmd("Step");
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	}
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	var nextLabelID = this.nextIndex++;
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	this.cmd("CreateLabel", nextLabelID, tree.data, tree.x, tree.y);
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	this.cmd("SetForegroundColor", nextLabelID, BST.PRINT_COLOR);
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	this.cmd("Move", nextLabelID, this.xPosOfNextLabel, this.yPosOfNextLabel);
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	this.cmd("Step");
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	this.xPosOfNextLabel +=  BST.PRINT_HORIZONTAL_GAP;
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	if (this.xPosOfNextLabel > this.print_max)
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	{
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		this.xPosOfNextLabel = BST.FIRST_PRINT_POS_X;
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		this.yPosOfNextLabel += BST.PRINT_VERTICAL_GAP;
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	}
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	if (tree.right != null)
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	{
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		this.cmd("Move", this.highlightID, tree.right.x, tree.right.y);
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		this.printTreeRec(tree.right);
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		this.cmd("Move", this.highlightID, tree.x, tree.y);	
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		this.cmd("Step");
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	}
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	return;
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}
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BST.prototype.findCallback = function(event)
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{
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	var findValue;
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	findValue = this.normalizeNumber(this.findField.value, 4);
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	this.findField.value = "";
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	this.implementAction(this.findElement.bind(this),findValue);						
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}
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BST.prototype.findElement = function(findValue)
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{
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	this.commands = [];
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	this.highlightID = this.nextIndex++;
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	this.doFind(this.treeRoot, findValue);
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	return this.commands;
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}
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BST.prototype.doFind = function(tree, value)
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{
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	this.cmd("SetText", 0, "正在搜索 "+value);
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	if (tree != null)
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	{
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		this.cmd("SetHighlight", tree.graphicID, 1);
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		if (tree.data == value)
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		{
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			this.cmd("SetText", 0, "正在搜索 "+value+":" + value + " = " + value + " (找不到元素)");
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			this.cmd("Step");					
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			this.cmd("SetText", 0, "已找到 :"+value);
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			this.cmd("SetHighlight", tree.graphicID, 0);
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		}
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		else
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		{
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			if (tree.data > value)
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			{
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				this.cmd("SetText", 0, "正在搜索 "+value+":" + value + " < " + tree.data + " (访问左子树)");
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				this.cmd("Step");
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				this.cmd("SetHighlight", tree.graphicID, 0);
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				if (tree.left!= null)
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				{
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					this.cmd("CreateHighlightCircle", this.highlightID, BST.HIGHLIGHT_CIRCLE_COLOR, tree.x, tree.y);
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					this.cmd("Move", this.highlightID, tree.left.x, tree.left.y);
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					this.cmd("Step");
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					this.cmd("Delete", this.highlightID);
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				}
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				this.doFind(tree.left, value);
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			}
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			else
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			{
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				this.cmd("SetText", 0, "正在搜索 "+value+":" + value + " > " + tree.data + " (访问右子树)");
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				this.cmd("Step");
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				this.cmd("SetHighlight", tree.graphicID, 0);
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				if (tree.right!= null)
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				{
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					this.cmd("CreateHighlightCircle", this.highlightID, BST.HIGHLIGHT_CIRCLE_COLOR, tree.x, tree.y);
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					this.cmd("Move", this.highlightID, tree.right.x, tree.right.y);
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					this.cmd("Step");
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					this.cmd("Delete", this.highlightID);				
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				}
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				this.doFind(tree.right, value);						
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			}
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		}
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	}
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	else
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	{
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		this.cmd("SetText", 0, "正在搜索 "+value+":" + "< 空树 > (找不到元素)");
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		this.cmd("Step");					
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		this.cmd("SetText", 0, "正在搜索 "+value+":" + " (找不到元素)");
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	}
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}
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BST.prototype.insertElement = function(insertedValue)
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{
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	this.commands = new Array();	
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	this.cmd("SetText", 0, "正在添加 "+insertedValue);
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	this.highlightID = this.nextIndex++;
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	if (this.treeRoot == null)
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	{
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		this.cmd("CreateCircle", this.nextIndex, insertedValue,  this.startingX, BST.STARTING_Y);
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		this.cmd("SetForegroundColor", this.nextIndex, BST.FOREGROUND_COLOR);
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		this.cmd("SetBackgroundColor", this.nextIndex, BST.BACKGROUND_COLOR);
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		this.cmd("Step");				
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		this.treeRoot = new BSTNode(insertedValue, this.nextIndex, this.startingX, BST.STARTING_Y)
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		this.nextIndex += 1;
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	}
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	else
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	{
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		this.cmd("CreateCircle", this.nextIndex, insertedValue, 100, 100);
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		this.cmd("SetForegroundColor", this.nextIndex, BST.FOREGROUND_COLOR);
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		this.cmd("SetBackgroundColor", this.nextIndex, BST.BACKGROUND_COLOR);
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		this.cmd("Step");				
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		var insertElem = new BSTNode(insertedValue, this.nextIndex, 100, 100)
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		this.nextIndex += 1;
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		this.cmd("SetHighlight", insertElem.graphicID, 1);
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		this.insert(insertElem, this.treeRoot)
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		this.resizeTree();				
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	}
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	this.cmd("SetText", 0, "");				
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	return this.commands;
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}
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BST.prototype.insert = function(elem, tree)
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{
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	this.cmd("SetHighlight", tree.graphicID , 1);
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	this.cmd("SetHighlight", elem.graphicID , 1);
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	if (elem.data < tree.data)
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	{
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		this.cmd("SetText", 0,  elem.data + " < " + tree.data + ",访问左子树");
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	}
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	else
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	{
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		this.cmd("SetText",  0, elem.data + " >= " + tree.data + ",访问右子树");
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	}
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	this.cmd("Step");
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	this.cmd("SetHighlight", tree.graphicID, 0);
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	this.cmd("SetHighlight", elem.graphicID, 0);
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	if (elem.data < tree.data)
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	{
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		if (tree.left == null)
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		{
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			this.cmd("SetText", 0, "左子树为null,添加元素");
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			this.cmd("SetHighlight", elem.graphicID, 0);
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			tree.left=elem;
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			elem.parent = tree;
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			this.cmd("Connect", tree.graphicID, elem.graphicID, BST.LINK_COLOR);
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		}
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		else
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		{
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			this.cmd("CreateHighlightCircle", this.highlightID, BST.HIGHLIGHT_CIRCLE_COLOR, tree.x, tree.y);
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			this.cmd("Move", this.highlightID, tree.left.x, tree.left.y);
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			this.cmd("Step");
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			this.cmd("Delete", this.highlightID);
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			this.insert(elem, tree.left);
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		}
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	}
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	else
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	{
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		if (tree.right == null)
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		{
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			this.cmd("SetText",  0, "右子树为null,添加元素");
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			this.cmd("SetHighlight", elem.graphicID, 0);
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			tree.right=elem;
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			elem.parent = tree;
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			this.cmd("Connect", tree.graphicID, elem.graphicID, BST.LINK_COLOR);
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			elem.x = tree.x + BST.WIDTH_DELTA/2;
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			elem.y = tree.y + BST.HEIGHT_DELTA
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			this.cmd("Move", elem.graphicID, elem.x, elem.y);
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		}
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		else
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		{
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			this.cmd("CreateHighlightCircle", this.highlightID, BST.HIGHLIGHT_CIRCLE_COLOR, tree.x, tree.y);
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			this.cmd("Move", this.highlightID, tree.right.x, tree.right.y);
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			this.cmd("Step");
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			this.cmd("Delete", this.highlightID);
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			this.insert(elem, tree.right);
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		}
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	}
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}
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BST.prototype.deleteElement = function(deletedValue)
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{
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	this.commands = [];
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	this.cmd("SetText", 0, "正在刪除 "+deletedValue);
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	this.cmd("Step");
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	this.cmd("SetText", 0, "");
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	this.highlightID = this.nextIndex++;
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	this.treeDelete(this.treeRoot, deletedValue);
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	this.cmd("SetText", 0, "");			
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	// Do delete
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	return this.commands;						
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}
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BST.prototype.treeDelete = function(tree, valueToDelete)
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{
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	var leftchild = false;
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	if (tree != null)
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	{
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		if (tree.parent != null)
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		{
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			leftchild = tree.parent.left == tree;
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		}
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		this.cmd("SetHighlight", tree.graphicID, 1);
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		if (valueToDelete < tree.data)
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		{	
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			this.cmd("SetText", 0, valueToDelete + " < " + tree.data + ", 访问左子树");
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		}
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		else if (valueToDelete > tree.data)
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		{
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			this.cmd("SetText",  0, valueToDelete + " > " + tree.data + ", 访问右子树");
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		}
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		else
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		{
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			this.cmd("SetText",  0, valueToDelete + " == " + tree.data + ".  Found node to delete");									
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		}
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		this.cmd("Step");
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		this.cmd("SetHighlight",  tree.graphicID, 0);
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		if (valueToDelete == tree.data)
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		{
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			if (tree.left == null && tree.right == null)
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			{
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				this.cmd("SetText", 0, "需要删除的是叶子节点,直接删除!");
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				this.cmd("Delete", tree.graphicID);
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				if (leftchild && tree.parent != null)
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				{
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					tree.parent.left = null;
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				}
 | 
						||
				else if (tree.parent != null)
 | 
						||
				{
 | 
						||
					tree.parent.right = null;
 | 
						||
				}
 | 
						||
				else
 | 
						||
				{
 | 
						||
					treeRoot = null;
 | 
						||
				}
 | 
						||
				this.resizeTree();				
 | 
						||
				this.cmd("Step");
 | 
						||
				
 | 
						||
			}
 | 
						||
			else if (tree.left == null)
 | 
						||
			{
 | 
						||
				this.cmd("SetText", 0, "需要删除的节点没有左子树.  \nSet parent of deleted node to right child of deleted node.");
 | 
						||
				if (tree.parent != null)
 | 
						||
				{
 | 
						||
					this.cmd("Disconnect",  tree.parent.graphicID, tree.graphicID);
 | 
						||
					this.cmd("Connect",  tree.parent.graphicID, tree.right.graphicID, BST.LINK_COLOR);
 | 
						||
					this.cmd("Step");
 | 
						||
					this.cmd("Delete", tree.graphicID);
 | 
						||
					if (leftchild)
 | 
						||
					{
 | 
						||
						tree.parent.left = tree.right;
 | 
						||
					}
 | 
						||
					else
 | 
						||
					{
 | 
						||
						tree.parent.right = tree.right;
 | 
						||
					}
 | 
						||
					tree.right.parent = tree.parent;
 | 
						||
				}
 | 
						||
				else
 | 
						||
				{
 | 
						||
					this.cmd("Delete", tree.graphicID);
 | 
						||
					this.treeRoot = tree.right;
 | 
						||
					this.treeRoot.parent = null;
 | 
						||
				}
 | 
						||
				this.resizeTree();				
 | 
						||
			}
 | 
						||
			else if (tree.right == null)
 | 
						||
			{
 | 
						||
				this.cmd("SetText", 0, "需要删除的节点没有右子树.  \nSet parent of deleted node to left child of deleted node.");
 | 
						||
				if (tree.parent != null)
 | 
						||
				{
 | 
						||
					this.cmd("Disconnect", tree.parent.graphicID, tree.graphicID);
 | 
						||
					this.cmd("Connect", tree.parent.graphicID, tree.left.graphicID, BST.LINK_COLOR);
 | 
						||
					this.cmd("Step");
 | 
						||
					this.cmd("Delete", tree.graphicID);
 | 
						||
					if (leftchild)
 | 
						||
					{
 | 
						||
						tree.parent.left = tree.left;								
 | 
						||
					}
 | 
						||
					else
 | 
						||
					{
 | 
						||
						tree.parent.right = tree.left;
 | 
						||
					}
 | 
						||
					tree.left.parent = tree.parent;
 | 
						||
				}
 | 
						||
				else
 | 
						||
				{
 | 
						||
					this.cmd("Delete",  tree.graphicID);
 | 
						||
					this.treeRoot = tree.left;
 | 
						||
					this.treeRoot.parent = null;
 | 
						||
				}
 | 
						||
				this.resizeTree();
 | 
						||
			}
 | 
						||
			else // tree.left != null && tree.right != null
 | 
						||
			{
 | 
						||
				this.cmd("SetText", 0, "需要删除的节点有2棵子树.  \n找到左子树中最大的节点.");
 | 
						||
				
 | 
						||
				this.highlightID = this.nextIndex;
 | 
						||
				this.nextIndex += 1;
 | 
						||
				this.cmd("CreateHighlightCircle", this.highlightID, BST.HIGHLIGHT_CIRCLE_COLOR, tree.x, tree.y);
 | 
						||
				var tmp = tree;
 | 
						||
				tmp = tree.left;
 | 
						||
				this.cmd("Move", this.highlightID, tmp.x, tmp.y);
 | 
						||
				this.cmd("Step");																									
 | 
						||
				while (tmp.right != null)
 | 
						||
				{
 | 
						||
					tmp = tmp.right;
 | 
						||
					this.cmd("Move", this.highlightID, tmp.x, tmp.y);
 | 
						||
					this.cmd("Step");																									
 | 
						||
				}
 | 
						||
				this.cmd("SetText", tree.graphicID, " ");
 | 
						||
				var labelID = this.nextIndex;
 | 
						||
				this.nextIndex += 1;
 | 
						||
				this.cmd("CreateLabel", labelID, tmp.data, tmp.x, tmp.y);
 | 
						||
				tree.data = tmp.data;
 | 
						||
				this.cmd("Move", labelID, tree.x, tree.y);
 | 
						||
				this.cmd("SetText", 0, "Copy largest value of left subtree into node to delete.");									
 | 
						||
				
 | 
						||
				this.cmd("Step");
 | 
						||
				this.cmd("SetHighlight", tree.graphicID, 0);
 | 
						||
				this.cmd("Delete", labelID);
 | 
						||
				this.cmd("SetText", tree.graphicID, tree.data);
 | 
						||
				this.cmd("Delete", this.highlightID);							
 | 
						||
				this.cmd("SetText", 0,"Remove node whose value we copied.");									
 | 
						||
				
 | 
						||
				if (tmp.left == null)
 | 
						||
				{
 | 
						||
					if (tmp.parent != tree)
 | 
						||
					{
 | 
						||
						tmp.parent.right = null;
 | 
						||
					}
 | 
						||
					else
 | 
						||
					{
 | 
						||
						tree.left = null;
 | 
						||
					}
 | 
						||
					this.cmd("Delete", tmp.graphicID);
 | 
						||
					this.resizeTree();
 | 
						||
				}
 | 
						||
				else
 | 
						||
				{
 | 
						||
					this.cmd("Disconnect", tmp.parent.graphicID,  tmp.graphicID);
 | 
						||
					this.cmd("Connect", tmp.parent.graphicID, tmp.left.graphicID, BST.LINK_COLOR);
 | 
						||
					this.cmd("Step");
 | 
						||
					this.cmd("Delete", tmp.graphicID);
 | 
						||
					if (tmp.parent != tree)
 | 
						||
					{
 | 
						||
						tmp.parent.right = tmp.left;
 | 
						||
						tmp.left.parent = tmp.parent;
 | 
						||
					}
 | 
						||
					else
 | 
						||
					{
 | 
						||
						tree.left = tmp.left;
 | 
						||
						tmp.left.parent = tree;
 | 
						||
					}
 | 
						||
					this.resizeTree();
 | 
						||
				}
 | 
						||
				
 | 
						||
			}
 | 
						||
		}
 | 
						||
		else if (valueToDelete < tree.data)
 | 
						||
		{
 | 
						||
			if (tree.left != null)
 | 
						||
			{
 | 
						||
				this.cmd("CreateHighlightCircle", this.highlightID, BST.HIGHLIGHT_CIRCLE_COLOR, tree.x, tree.y);
 | 
						||
				this.cmd("Move", this.highlightID, tree.left.x, tree.left.y);
 | 
						||
				this.cmd("Step");
 | 
						||
				this.cmd("Delete", this.highlightID);
 | 
						||
			}
 | 
						||
			this.treeDelete(tree.left, valueToDelete);
 | 
						||
		}
 | 
						||
		else
 | 
						||
		{
 | 
						||
			if (tree.right != null)
 | 
						||
			{
 | 
						||
				this.cmd("CreateHighlightCircle", this.highlightID, BST.HIGHLIGHT_CIRCLE_COLOR, tree.x, tree.y);
 | 
						||
				this.cmd("Move", this.highlightID, tree.right.x, tree.right.y);
 | 
						||
				this.cmd("Step");
 | 
						||
				this.cmd("Delete", this.highlightID);
 | 
						||
			}
 | 
						||
			this.treeDelete(tree.right, valueToDelete);
 | 
						||
		}
 | 
						||
	}
 | 
						||
	else
 | 
						||
	{
 | 
						||
		this.cmd("SetText", 0, "元素 "+valueToDelete+" 未找到, 无法删除");
 | 
						||
	}
 | 
						||
	
 | 
						||
}
 | 
						||
 | 
						||
BST.prototype.resizeTree = function()
 | 
						||
{
 | 
						||
	var startingPoint  = this.startingX;
 | 
						||
	this.resizeWidths(this.treeRoot);
 | 
						||
	if (this.treeRoot != null)
 | 
						||
	{
 | 
						||
		if (this.treeRoot.leftWidth > startingPoint)
 | 
						||
		{
 | 
						||
			startingPoint = this.treeRoot.leftWidth;
 | 
						||
		}
 | 
						||
		else if (this.treeRoot.rightWidth > startingPoint)
 | 
						||
		{
 | 
						||
			startingPoint = Math.max(this.treeRoot.leftWidth, 2 * startingPoint - this.treeRoot.rightWidth);
 | 
						||
		}
 | 
						||
		this.setNewPositions(this.treeRoot, startingPoint, BST.STARTING_Y, 0);
 | 
						||
		this.animateNewPositions(this.treeRoot);
 | 
						||
		this.cmd("Step");
 | 
						||
	}
 | 
						||
	
 | 
						||
}
 | 
						||
 | 
						||
BST.prototype.setNewPositions = function(tree, xPosition, yPosition, side)
 | 
						||
{
 | 
						||
	if (tree != null)
 | 
						||
	{
 | 
						||
		tree.y = yPosition;
 | 
						||
		if (side == -1)
 | 
						||
		{
 | 
						||
			xPosition = xPosition - tree.rightWidth;
 | 
						||
		}
 | 
						||
		else if (side == 1)
 | 
						||
		{
 | 
						||
			xPosition = xPosition + tree.leftWidth;
 | 
						||
		}
 | 
						||
		tree.x = xPosition;
 | 
						||
		this.setNewPositions(tree.left, xPosition, yPosition + BST.HEIGHT_DELTA, -1)
 | 
						||
		this.setNewPositions(tree.right, xPosition, yPosition + BST.HEIGHT_DELTA, 1)
 | 
						||
	}
 | 
						||
	
 | 
						||
}
 | 
						||
BST.prototype.animateNewPositions = function(tree)
 | 
						||
{
 | 
						||
	if (tree != null)
 | 
						||
	{
 | 
						||
		this.cmd("Move", tree.graphicID, tree.x, tree.y);
 | 
						||
		this.animateNewPositions(tree.left);
 | 
						||
		this.animateNewPositions(tree.right);
 | 
						||
	}
 | 
						||
}
 | 
						||
 | 
						||
BST.prototype.resizeWidths = function(tree) 
 | 
						||
{
 | 
						||
	if (tree == null)
 | 
						||
	{
 | 
						||
		return 0;
 | 
						||
	}
 | 
						||
	tree.leftWidth = Math.max(this.resizeWidths(tree.left), BST.WIDTH_DELTA / 2);
 | 
						||
	tree.rightWidth = Math.max(this.resizeWidths(tree.right), BST.WIDTH_DELTA / 2);
 | 
						||
	return tree.leftWidth + tree.rightWidth;
 | 
						||
}
 | 
						||
 | 
						||
 | 
						||
 | 
						||
 | 
						||
function BSTNode(val, id, initialX, initialY)
 | 
						||
{
 | 
						||
	this.data = val;
 | 
						||
	this.x = initialX;
 | 
						||
	this.y = initialY;
 | 
						||
	this.graphicID = id;
 | 
						||
	this.left = null;
 | 
						||
	this.right = null;
 | 
						||
	this.parent = null;
 | 
						||
}
 | 
						||
 | 
						||
BST.prototype.disableUI = function(event)
 | 
						||
{
 | 
						||
	this.insertField.disabled = true;
 | 
						||
	this.insertButton.disabled = true;
 | 
						||
	this.deleteField.disabled = true;
 | 
						||
	this.deleteButton.disabled = true;
 | 
						||
	this.findField.disabled = true;
 | 
						||
	this.findButton.disabled = true;
 | 
						||
	this.printButton.disabled = true;
 | 
						||
}
 | 
						||
 | 
						||
BST.prototype.enableUI = function(event)
 | 
						||
{
 | 
						||
	this.insertField.disabled = false;
 | 
						||
	this.insertButton.disabled = false;
 | 
						||
	this.deleteField.disabled = false;
 | 
						||
	this.deleteButton.disabled = false;
 | 
						||
	this.findField.disabled = false;
 | 
						||
	this.findButton.disabled = false;
 | 
						||
	this.printButton.disabled = false;
 | 
						||
}
 | 
						||
 | 
						||
 | 
						||
var currentAlg;
 | 
						||
 | 
						||
function init()
 | 
						||
{
 | 
						||
	var animManag = initCanvas();
 | 
						||
	currentAlg = new BST(animManag, canvas.width, canvas.height);
 | 
						||
	
 | 
						||
} |