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<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>二叉树算法</title>
<script type="text/javascript">
window.onload = function () {
function Node(data, left, right) {
this.data = data;
this.left = left;
this.right = right;
}
Node.prototype.show = function() {
return this.data;
}
//建立一个二叉树
function BST() {
this.root = null;
}
//二叉树的插入操作
BST.prototype.insert = function(data) {
var n = new Node(data, null, null);
if(this.root === null) {
this.root = n;
}else {
var current = this.root;
var parent;
while(true) {
parent = current;
if(data < current.data) {
current = current.left;
if(current === null) {
parent.left = n;
break;
}
}else {
current = current.right;
if(current === null) {
parent.right = n;
break;
}
}
}
}
}
//二叉树的历遍操作
BST.prototype.inOrder = function(node) {
if(!(node === null)) {
this.inOrder(node.left);
console.log(node.show());
this.inOrder(node.right);
}
}//中序历遍
BST.prototype.preOrder = function(node) {
if(!(node === null)) {
console.log(node.show());
this.inOrder(node.left);
this.inOrder(node.right);
}
}//先序历遍
BST.prototype.postOrder = function(node) {
if(!(node === null)) {
this.inOrder(node.left);
this.inOrder(node.right);
console.log(node.show());
}
}//后序历遍
BST.prototype.getMin = function() {
var current = this.root;
while(!(current.left === null)) {
current = current.left;
}
return current.data;
}//获取最小值
BST.prototype.getMax = function() {
var current = this.root;
while(!(current.right === null)) {
current = current.right;
}
return current.data;
}//获取最大值
BST.prototype.find = function(data) {
var current = this.root;
while(current !== null) {
if(current.data === data) {
return current.data;
}else if(data < current.data) {
current = current.left;
}else {
current = current.right;
}
}
return null;
}//查找节点
BST.prototype.getSmallest = function(node) {
if (node.left == null) {
return node;
}
else {
return this.getSmallest(node.left);
}
}
//删除一个节点，需要传入一个root节点(根节点)
BST.prototype.remove = function(node, data) {
if(node === null) {
return null;
}
if(data == node.data) {
if(node.left === null && node.right === null) {
return null;
}
if(node.left === null) {
return node.right;
}
if(node.right === null) {
return node.left;
}
var tempNode = this.getSmallest(node.right);
node.data = tempNode.data;
node.right = remove(node.right, tempNode.data);
return node;
}else if(data < node.data) {
node.left = this.remove(node.left, data);
return node;
}else {
node.right = this.remove(node.right, data);
return node;
}
}
var num = new BST();
num.insert(23);
num.insert(45);
num.insert(16);
num.insert(37);
num.insert(3);
num.insert(99);
num.insert(22);
//console.log(num.root);
//num.inOrder(num.root);
//console.log(num.getMin());
//console.log(num.getMax());
num.inOrder(num.root);
console.log(num.remove(num.root,37));
num.inOrder(num.root);
}
</script>
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