0 Build a binary tree from a given preorder traversal 0 Preorder and Reverse Preorder Binary Tree Traversals 0 Construction of Binary Search Tree from preorder traversal iteratively (not recursion) 1 Binary search tree iterative preorder traversal without additional storage 0 Constructing Bi...
*/// 由于主函数的形式已经符合分治法需要的形式(具有合适的返回值),直接使用主函数做为递归函数vector<int>preorderTraversal(TreeNode * root){//递归三要素之定义// write your code herevector<int> result;if(root == nullptr) {returnresult;// 递归三要素之出口}// 获取左子树的遍历结果vector<int> ...
View Code b、下面代码实现较简洁(个人感觉,不喜勿喷) View Code
* TreeNode(int x) : val(x), left(NULL), right(NULL) {} 8 * }; 9 */ 10 class Solution { 11 public: 12 vector<int> preorderTraversal(TreeNode *root) { 13 vector<int> root_vec; 14 vector<int> left_vec; 15 vector<int>...
/** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */ class Solution { public: vector<int> preorderTraversal(TreeNode* root) { vector<int> ret; pre...
每天一算:Binary Tree Preorder Traversal 程序员吴师兄 + 关注 预计阅读时间2分钟 LeetCode上第144 号问题:二叉树的前序遍历 题目 给定一个二叉树,返回它的 前序 遍历。 示例: 输入: [1,null,2,3] 输出: [1,2,3] 进阶: 递归算法很简单,你可以通过迭代算法完成吗? 解题思路 用栈(Stack)的思路来...
https://leetcode.com/problems/binary-tree-preorder-traversal/description/ 中文版描述 给你二叉树的根节点 root ,返回它节点值的 前序遍历。 示例1: 输入:root = [1,null,2,3] 输出:[1,2,3] 示例2: 输入:root = [] 输出:[] 示例3: 输入:root = [1] 输出:[1] 示例4: 输入:root = [1...
Given a binary tree, return the preorder traversal of its nodes' values. Example: Input: [1,null,2,3] 1 2 / 3 Output: [1,2,3] Follow up: Recursive solution is trivial, could you do it iteratively? 翻译 给出一棵二叉树,返回其节点值的前序遍历。
LeetCode——Binary Tree Preorder Traversal Given a binary tree, return thepreordertraversal of its nodes' values. For example: Given binary tree{1,#,2,3}, 1 \ 2 / 3 1. 2. 3. 4. 5. return[1,2,3]. Note:Recursive solution is trivial, could you do it iteratively?
代码 # Definition for a binary tree node.# class TreeNode(object):# def __init__(self, x):# self.val = x# self.left = None# self.right = NoneclassSolution(object):defpreorderTraversal(self,root):""" :type root: TreeNode