原题链接在此:https://leetcode.com/problems/binary-tree-level-order-traversal/ Given therootof a binary tree, returnthe level order traversal of its nodes' values. (i.e., from left to right, level by level). 给你一个二叉树,请你返回其按 层序遍历 得到的节点值。 (即逐层地,从左到右访...
否则,我们应访访问当前节点的右孩子(入栈)。 // C++ CODE: classSolution {public: vector<int> postorderTraversal(TreeNode*root) { stack<TreeNode*>s; vector<int>result;while(root){ s.push(root); root= root->left; }while(!s.empty()){ TreeNode* tmp =s.top();if(tmp->right){if(resu...
1 struct TreeNode { 2 int val; 3 TreeNode* left; 4 TreeNode* right; 5 TreeNode(int x): val(x), left(NULL),right(NULL) {} 6 }; 7 8 void Swap(vector<int> &ivec) 9 { 10 int temp = 0; 11 int len = ivec.size(); 12 for (int i = 0; i < len/2; i ++) { 13...
Leetcode 144 binary tree preorder traversal 下面这种写法使用了一个辅助结点p,这种写法其实可以看作是一个模版,对应的还有中序和后序的模版写法,形式很统一,方便于记忆。 辅助结点p初始化为根结点,while循环的条件是栈不为空或者辅助结点p不为空,在循环中首先判断如果辅助结点p存在,那么先将p加入栈中,然后将...
Given a binary tree, return the level order traversal of its nodes' values. (ie, from left to right, level by level). For example: Given binary tree [3,9,20,null,null,15,7], 代码语言:javascript 代码运行次数:0 运行 AI代码解释 ...
Can you solve this real interview question? Binary Tree Level Order Traversal - Given the root of a binary tree, return the level order traversal of its nodes' values. (i.e., from left to right, level by level). Example 1: [https://assets.leetcode.c
方法一: 使用 LeetCode: 102. Binary Tree Level Order Traversal 的方法。在偶数次写入时,翻转写入的序列。 方法二: 使用两个栈存每行的数据,奇数行先存左孩子,再存右孩子,偶数行先存右孩子,再存左孩子。 AC 代码 方法一 /** ...
classSolution{public:vector<vector<int>>zigzagLevelOrder(TreeNode*root){vector<vector<int>>ret;queue<TreeNode*>current,next;//利用两个队列的交替来区分每一层boolisRe=false;vector<int>v;if(root==NULL)returnret;current.push(root);while(!current.empty()){TreeNode*tmp=current.front();current....
It's essential to be mindful of boundary conditions when invoking the recursive function. 3. Code: Lists as parameters Indices as parameters High efficiency indices as parameters 3.1. Explaination of the Code: 3.1.1 Lists as parameters: Start by defining the function buildTree that takes the...
94. Binary Tree Inorder TraversalEasy Topics Companies Given the root of a binary tree, return the inorder traversal of its nodes' values. Example 1: Input: root = [1,null,2,3] Output: [1,3,2] Explanation: Example 2: Input: root = [1,2,3,4,5,null,8,null,null,6,7,9] ...