非递归代码如下: 1publicArrayList<Integer> inorderTraversal(TreeNode root) { 2ArrayList<Integer> res =newArrayList<Integer>(); 3if(root ==null) 4returnres; 5LinkedList<TreeNode> stack =newLinkedList<TreeNode>(); 6while(root!=null|| !stack.isEmpty()){ 7if(root!=null){ 8stack.push(root...
1/**2* Definition for a binary tree node.3* public class TreeNode {4* int val;5* TreeNode left;6* TreeNode right;7* TreeNode(int x) { val = x; }8* }9*/10publicclassSolution {11publicList<Integer>inorderTraversal(TreeNode root) {12List<Integer> ls =newArrayList<Integer>();13...
private void pushAllTheLeft(Stack<TreeNode> s, TreeNode root){ s.push(root); while(root.left!=null){ root = root.left; s.push(root); } } } Binary Tree Postorder Traversal Given a binary tree, return the postorder traversal of its nodes' values. For example: Given binary tree {1,...
left(NULL), right(NULL) {} * }; */ class Solution { public: vector<int> inorderTraversal(TreeNode* root) { vector<int> ret; if(nullptr == root) return ret; inOrder(root, ret); return ret; } private: void inOrder(TreeNode* root, vector<int>& ret) { ...
Given preorder and inorder traversal of a tree, construct the binary tree. 二分法 复杂度 时间O(N^2) 空间 O(N) 思路 我们先考察先序遍历序列和中序遍历序列的特点。对于先序遍历序列,根在最前面,后面部分存在一个分割点,前半部分是根的左子树,后半部分是根的右子树。对于中序遍历序列,根在中间部分...
1. Problem Descriptions:Given two integer arrays inorderandpostorderwhereinorderis the inorder traversal of a binary tree andpostorderis the postorder traversal of the same tree, construct and retu…
名字叫做, morrois traversal, 自己写了下: My code: /** * Definition for a binary tree node. * public class TreeNode { * int val; * TreeNode left; * TreeNode right; * TreeNode(int x) { val = x; } * } */publicclassSolution{publicList<Integer>inorderTraversal(TreeNoderoot){List...
这道题和LeetCode笔记:107. Binary Tree Level Order Traversal II是姊妹题,解题思路都是一样的,只是结果要求的顺序是反的,同样有两种方法,也就是经常说到的DFS深度优先遍历和BFS广度优先遍历。 BFS: 广度优先遍历就是一层层地攻略过去,把每一层的所有节点都记录下来再走向下一层。因为每层会有多个节点,不是简...
102. 二叉树的层序遍历 - 给你二叉树的根节点 root ,返回其节点值的 层序遍历 。 (即逐层地,从左到右访问所有节点)。 示例 1: [https://assets.leetcode.com/uploads/2021/02/19/tree1.jpg] 输入:root = [3,9,20,null,null,15,7] 输出:[[3],[9,20],[15,7]]
Binary Tree Zigzag Level Order Traversal.md Verified 4300b6d colorbox mentioned this pull request Mar 1, 2025 103. Binary Tree Zigzag Level Order Traversal colorbox/leetcode#41 Open Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment ...