JavaScript数据结构之 二叉排序树

/** * 二叉排序树（Binary Sort Tree）又称二叉查找树（Binary Search Tree），亦称二叉搜索树。 * 左边子节点的值 < 父节点的值 < 右边子节点的值 * 包括的方法有：插入、遍历、查询、查询父节点、右树上最小节点、 * 前中后序遍历、清空、删除、是否为空、求宽度、求深度 */function BinarySortTree(value){    this.root = null;    if(typeof value === "number"){        this.root = this.insert(value);    }else{        return false;    }}BinarySortTree.prototype = {    //创建节点    createNode: function(value){        return {            value:value,            left:null,            right:null        };    },    //插入一个新节点，如果没有root就创建root    insert: function(value){        if(typeof value !== "number"){            return false;        }        var node = this.createNode(value);        if(!this.root){            this.root = node;            return this.root;        }else{            return this.insertNode(this.root, node);        }    },    //通过递归来插入    insertNode: function(fNode, newNode){        if(fNode.value>newNode.value){            if(fNode.left===null){                fNode.left = newNode;                return newNode;            }else{                return this.insertNode(fNode.left, newNode);            }        }else if(fNode.value<newNode.value){            if(fNode.right===null){                fNode.right = newNode;                return newNode;            }else{                return this.insertNode(fNode.right, newNode);            }        }else{            return false;        }    },    //查找第一个值相同的节点    findFirst: function(value){        console.log(this.root);        if(!this.root)return false;        return this.findFirstNode(this.root, value)    },    //采用的是前序查找 中>左>右    findFirstNode: function(node, value){        if(node === null)return false;        if(node.value === value)return node;        else if(node.value > value){            return this.findFirstNode(node.left, value);        }        else{            return this.findFirstNode(node.right, value);        }    },    //判断空树    isEmpty: function(){        if(this.root)return false;        return true;    },    //清空二叉树    clear: function(){        this.clearTree(this.root);        this.root = null;    },    //清理某个子树, 需要找到父节点，然后设为null，不能直接将node设为null    clearTree: function(node){        if(node === null)return;        this.clearTree(node.left);        this.clearTree(node.right);        var fNode = this.findFather(node);        if(fNode.left === node)fNode.left=null;        else if(fNode.right === node)fNode.right=null;    },    //寻找父节点    findFather: function(node){        return this.findFatherNode(this.root,node);    },    findFatherNode: function(fNode, node){        if(fNode===null)return false;        if(fNode.left === node || fNode.right === node)return fNode;        if(fNode.value>node.value)return this.findFatherNode(fNode.left, node);        else return this.findFatherNode(fNode.right, node);    },    //计算二叉树深度    getDepth: function(){        return this.getTreeDepth(this.root);    },    //计算子树深度    getTreeDepth: function(node){        if(node === null)return 0;        var leftDepth = this.getTreeDepth(node.left) + 1;        var rightDepth = this.getTreeDepth(node.right) + 1;        if(leftDepth>rightDepth)            return leftDepth;        return rightDepth;    },    //计算树的宽度    getWidth: function(){        return this.getLeftTreeWidth(this.root)+this.getRightTreeWidth(this.root)-1;    },    //计算子树宽度    getLeftTreeWidth: function(node){        if(node === null)return 0;        return 1+this.getLeftTreeWidth(node.left);    },    getRightTreeWidth: function(node){        if(node === null)return 0;        return 1+this.getRightTreeWidth(node.right);    },    //前序遍历    preOrderTraverse: function(callback){        this.preOrderTraverseNode(this.root, callback);    },    preOrderTraverseNode: function(node, callback){        if(node === null)return;        //left        this.preOrderTraverseNode(node.left, callback);        //callback        callback(node.value);        //right        this.preOrderTraverseNode(node.right, callback);    },    //中序遍历    inOrderTraverse: function(callback){        this.inOrderTraverseNode(this.root, callback);    },    inOrderTraverseNode: function(node, callback){        if(node === null)return;        //callback        callback(node.value);        //left        this.inOrderTraverseNode(node.left, callback);        //right        this.inOrderTraverseNode(node.right, callback);    },    //后序遍历    postOrderTraverse: function(callback){        this.postOrderTraverseNode(this.root, callback);    },    postOrderTraverseNode: function(node, callback){        if(node === null)return;        //left        this.postOrderTraverseNode(node.left, callback);        //right        this.postOrderTraverseNode(node.right, callback);        //callback        callback(node.value);    },    //找到右树的最小值    findRightMinNode: function(node){        if(node.left===null)return node;        else return this.findRightMinNode(node.left);    },    //移除    remove: function(value){        return this.removeNode(this.root, value);    },    removeNode: function(node, value){        var targetNode = this.findFirstNode(node, value);        var fNode = this.findFather(targetNode);        if(targetNode===this.root){            return false;//暂不考虑移除根节点情况        }        //target为叶子节点        if(targetNode.left===null&&targetNode.right===null){            fNode.left === targetNode?fNode.left=null:fNode.right=null;            return true;        }        //target只有一个子节点        if(targetNode.left===null&&targetNode.right){            fNode.left === targetNode?fNode.left=targetNode.right:fNode.right=targetNode.right;            delete targetNode.value;            delete targetNode.right;            delete targetNode.left;            return true;        }        if(targetNode.right===null&&targetNode.left){            fNode.left === targetNode?fNode.left=targetNode.left:fNode.right=targetNode.left;            delete targetNode.value;            delete targetNode.right;            delete targetNode.left;            return true;        }        //target有两个子节点        var minNode = this.findRightMinNode(targetNode.right);        targetNode.value = minNode.value;        return this.removeNode(targetNode.right, targetNode.value);    }};var root = new BinarySortTree(0);root.insert(1);root.insert(2);root.insert(8);root.insert(4);root.insert(9);root.insert(-7);root.insert(-1);root.insert(-8);console.log(root);