Javascript实现二叉搜索树

class Node {                                    //节点结构  constructor(data, left, right) {    this.data = data;    this.left = left;    this.right = right;  }}class BinarySearchTree {                        //二叉树、添加节点、删除节点、查询节点  constructor() {    this.root = null;  }  insert(data) {    let n = new Node(data, null, null);    if (!this.root) {      return this.root = n;    }    let currentNode = this.root;    let parent = null;    while (1) {      parent = currentNode;      if (data < currentNode.data) {        currentNode = currentNode.left;        if (currentNode === null) {          parent.left = n;          break;        }      } else {        currentNode = currentNode.right;        if (currentNode === null) {          parent.right = n;          break;        }      }    }  }  remove(data) {    this.root = this.removeNode(this.root, data)  }  removeNode(node, data) {    if (node == null) {      return null;    }    if (data == node.data) {      // no children node      if (node.left == null && node.right == null) {        return null;      }      if (node.left == null) {        return node.right;      }      if (node.right == null) {        return node.left;      }      let getSmallest = function(node) {        if(node.left === null && node.right == null) {          return node;        }        if(node.left != null) {          return node.left;        }        if(node.right !== null) {          return getSmallest(node.right);        }      }      let temNode = getSmallest(node.right);      node.data = temNode.data;      node.right = this.removeNode(temNode.right,temNode.data);      return node;    } else if (data < node.data) {      node.left = this.removeNode(node.left,data);      return node;    } else {      node.right = this.removeNode(node.right,data);      return node;    }  }  find(data) {    var current = this.root;    while (current != null) {      if (data == current.data) {        break;      }      if (data < current.data) {        current = current.left;      } else {        current = current.right      }    }    return current.data;  }}module.exports = BinarySearchTree;