数据结构与算法JavaScript描述读书笔记（js实现树）

js定义二叉查找树

//创建构造函数创建节点
function Node(data){
    this.data = data;
    this.left = null;
    this.right = null;
}
function tree(){
    this.root = null;
    this.insert = insert;
    this.inOrder = inOrder;
    this.preOrder = preOrder;
    this.postOrder = postOrder;
}
function insert(data){
    var n = new Node(data);
    if(this.root == null){
        this.root = n;
    }else{
        var cur = this.root;
        while (true){
            if(data < cur.data){
                if(cur.left == null){
                    cur.left = n;
                    break;
                }else{
                    cur = cur.left;
                }
            }else{
                if(cur.right == null){
                    cur.right = n;
                    break;
                }else{
                    cur = cur.right;
                }
            }
        }
    }
}
//中序遍历
function inOrder(node){
    var str = '';
    if(node != null){
        inOrder(node.left);
        str = node.data;
        console.log(str);
        inOrder(node.right);
    }
}
//先序遍历
function preOrder(node){
    var str = '';
    if(node != null){
        str = node.data;
        console.log(str);
        preOrder(node.left);
        preOrder(node.right);
    }
}
//后序遍历
function postOrder(node){
    var str = '';
    if(node != null){
        postOrder(node.left);
        postOrder(node.right);
        str = node.data;
        console.log(str);
    }
}

查找最小值最大值

思路：遍历左子树，取最后一个值，得到最小值；遍历右子树，取最后一个值，得到最大值

function getMin(){
    var cur = this.root;
    while (cur.left != null){
        cur = cur.left;
    }
    return cur.data;
}
function getMax(){
    var cur = this.root;
    while (cur.right != null){
        cur = cur.right;
    }
    return cur.data;
}

查找给定值

function find(data){
    var cur = this.root;
    while(cur != null){
        if(cur.data == data){
            return true;
        }else if(cur.data < data){
            cur = cur.right;
        }else{
            cur = cur.left;
        }
    }
    return false;
}