js数据结构——平衡查找树

超详细超清楚的红黑树解析

2-3查找树

插入原理图

红黑二叉查找树

与2-3查找树的联系
将树中的链接分为两种类型，红链接将两个2-结点连接起来构成一个3-结点，黑色则是普通链接。
定义：
1. 红链接均为左链接
2. 没有任何一个结点同时和两条红链接相连
3. 该树是完美黑色平衡的，即任意空链接到根节点的路径上的黑链接数量相同。
该定义与的红黑树与相应的2-3树为一一对应

**根结点总是黑色的

• 左旋和右旋
  

function rotateLeft (node) {
    let x = node.right;
    node.right = x.left;
    x.left = node;
    x.color = node.color;
    node.color = RED;
    x.N = node.N;
    node.N = 1 + size(node.left) + size(node.right);
    return x;
}

function rotateRight (node) {
    let x = node.left;
    x.left = node.right;
    x.right = node;
    x.color = node.color;
    node.color = RED;
    x.N = node.N;
    h.N = 1 + size(node.right) + size(node.left);
}

const RED = true;
const BLACK = false;
class Node {
    constructor (key, value) {
        this.key = key;
        this.value = value;
        this.N = 1;
        this.color = RED;//其父结点指向他的链接的颜色，红色为true，黑色为false；  
        this.left = null;
        this.right = null;
    }
}
class RedBlackBST  {
    constructor () {
        this.root = null;
    }
    isRed (node) {
        return node && node.color || false;
    }
    put (node, key, value) {
        if (arguments.length === 2) {
            return this.put(this.root, key, value);
        } 
        if(node === null){
            let x = new Node(key, value);
            return x;
        }
        let cmp = compare(key, node.key);
        if (cmp > 0) {
            node.left = this.put(node.left, key, value);
        } else if (cmp < 0) {
            node.right = this.put (node.right, key, value);
        } else {
            node.value = value;
        }
        if(this.isRed(node.left) && this.isRed(node.right)) {
            this.flipColors(node);
            return node;
        }
        if(this.isRed(node.left) && this.isRed(node.left.left)){
            let x = this.rotateRight
        }

    }
}
RedBlackBST.prototype.rotateLeft = rotateLeft;
RedBlackBST.prototype.rotaterRight = rotateRight;
RedBlackBST.prototype.flipColors = flipColors;
RedBlackBST.prototype.size = size;
function rotateLeft (node) {
    let x = node.right;
    node.right = x.left;
    x.left = node;
    x.color = node.color;
    node.color = RED;
    x.N = node.N;
    node.N = 1 + this.size(node.left) + this.size(node.right);
    return x;
}

function rotateRight (node) {
    let x = node.left;
    x.left = node.right;
    x.right = node;
    x.color = node.color;
    node.color = RED;
    x.N = node.N;
    h.N = 1 + this.size(node.right) + this.size(node.left);
    return x;
}

function flipColors (node) {
    node.left.color = BLACK;
    node.right.color = BLACK;
    node.color = RED;
}
function size (node) {
    return node ? node.N : 0;
}
function compare (key1, key2){
    if (key1 < key2) {
        return 1;
    }
    if (key1 === key2) {
        return 0;
    }
    if (key1 > key2) {
        return -1;
    }

}