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...
Morris Traversal方法遍历二叉树(非递归,不用栈,O(1)空间) /** * Definition for a binary tree node. * public class TreeNode { * int val; * TreeNode left; * TreeNode right; * TreeNode(int x) { val = x; } * } */ import java.util.List; import java.util.ArrayList; import java.u...
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,...
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...
* TreeNode right; * TreeNode(int x) { val = x; } * } */publicclassSolution{public List<Integer>inorderTraversal(TreeNode root){ArrayList<Integer>result=newArrayList<Integer>();if(root==null)returnresult;inorderTraversal(root,result);returnresult;}privatevoidinorderTraversal(TreeNode root,Arra...
*/classSolution{public List<Integer>inorderTraversal(TreeNode root){List<Integer>result=newLinkedList<>();TreeNode current=root;TreeNode prev=null;while(current!=null){// left firstif(current.left==null){result.add(current.val);current=current.right;}// if there is left, get the rightmost...
Binary tree traversal: Preorder, Inorder, and Postorder In order to illustrate few of the binary tree traversals, let us consider the below binary tree: Preorder traversal: To traverse a binary tree in Preorder, following operations are carried-out (i) Visit the root, (ii) Traverse the le...
Your air compressor... Bertlinsheng 0 272 Flatten Binary Tree to Linked List 2019-12-21 22:15 − Description Flatten a binary tree to a fake "linked list" in pre-order traversal. Here we use the right pointer in TreeNode as the ... YuriFLAG 0 235 [Hadoop] Zookeeper ...
publicList<Integer>inorderTraversal3(TreeNoderoot){List<Integer>ans=newArrayList<>();TreeNodecur=root;while(cur!=null){//情况 1if(cur.left==null){ans.add(cur.val);cur=cur.right;}else{//找左子树最右边的节点TreeNodepre=cur.left;while(pre.right!=null&&pre.right!=cur){pre=pre.right;}...
Leetcode 94: Binary Tree Inorder Traversal-中序遍历 自动驾驶搬砖师 一步一个台阶,一天一个脚印 一、题目描述 给定一个二叉树,返回它的中序遍历。 二、解题思路 2.1 递归法 时间复杂度 O(n) 空间复杂度 O(n) 2.2 迭代法 时间复杂度 O(n) 空间复杂度 O(n)(1) 同理创建一个Stack,然后按左/中/右...