Lintcode：在二叉查找树中插入节点

问题：

给定一棵二叉查找树和一个新的树节点，将节点插入到树中。

你需要保证该树仍然是一棵二叉查找树。

样例：

样例 1: 输入: tree = {}, node= 1 输出: {1} 样例解释: 在空树中插入一个点，应该插入为根节点。 样例 2: 输入: tree = {2,1,4,3}, node = 6 输出: {2,1,4,3,6} 样例解释: 如下： 2 2 / \ / \ 1 4 --> 1 4 / / \ 3 3 6

python：

""" Definition of TreeNode: class TreeNode: def __init__(self, val): self.val = val self.left, self.right = None, None """ class Solution: """ @param: root: The root of the binary search tree. @param: node: insert this node into the binary search tree @return: The root of the new binary search tree. """ def insertNode(self, root, node): # write your code here if root == None: root = node return root temp = root while temp != None: if node.val < temp.val: if temp.left != None: temp = temp.left continue else: temp.left = node return root else: if temp.right != None: temp = temp.right continue else: temp.right = node return root return root

 

C++：

/** * Definition of TreeNode: * class TreeNode { * public: * int val; * TreeNode *left, *right; * TreeNode(int val) { * this->val = val; * this->left = this->right = NULL; * } * } */ class Solution { public: /* * @param root: The root of the binary search tree. * @param node: insert this node into the binary search tree * @return: The root of the new binary search tree. */ TreeNode * insertNode(TreeNode * root, TreeNode * node) { // write your code here if(root == NULL) { root = node; return root; } TreeNode *temp = root; while(temp != NULL) { if(node->val < temp->val) { if(temp->left != NULL) { temp = temp->left;; continue; }else{ temp->left = node; return root; } }else{ if(temp->right != NULL) { temp = temp->right; continue; }else{ temp->right = node; return root; } } } return root; } };