1classSolution {2public:3vector<int> postorderTraversal(TreeNode *root) {4vector<int>result;5stack<TreeNode *>s;6TreeNode *p =root;7TreeNode *q = nullptr, *last =nullptr;8while(!s.empty() ||p) {9if(p) {10s.push(p);11p = p->left;12}else{13q =s.top();14if(q->right &...
二叉树遍历(Binary Tree Traversal) 二叉树的递归遍历比较简单,这里说一下非递归遍历,以中序遍历为例子。 非递归遍历主要用到栈来协助进行。对于一个二叉树,首先根节点入栈,如果有左儿子,则继续入栈,重复直到最左边的儿子,这时候此节点值为要遍历的第一个值,他父亲是在栈顶。所以我们做一次出栈操作 f = stack...
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: Input: root = [3,9,20,null,null,15,7] Output: [[3],[9,20],[15,7]] Example 2: Input: root = [1] Output: [[1]] Example ...
publicList<Integer>inorderTraversal(TreeNoderoot){List<Integer>ans=newArrayList<>();Stack<TreeNode>stack=newStack<>();TreeNodecur=root;while(cur!=null||!stack.isEmpty()){//节点不为空一直压栈while(cur!=null){stack.push(cur);cur=cur.left;//考虑左子树}//节点为空,就出栈cur=stack.pop()...
Implementation of Inorder, Preorder, and Postorder traversal or a binary tree / binary search tree. Learn to implement binary tree traversal methods: Inorder, Preorder, and Postorder. Code examples are provided for traversing nodes in specific orders in
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 ...
Tree traversalis the process of visiting each node in the tree exactly once. Visiting each node in a graph should be done in a systematic manner. If search result in a visit to all the vertices, it is called a traversal. There are basically three traversal techniques for a binary tree th...
If we are given a binary tree and we need to perform a vertical order traversal, that means we will be processing the nodes of the binary tree from left to right. Suppose we have a tree such as the one given below. If we traverse the tree in vertical order and print the nodes then...
Tree Traversal 從root開始,使用某種特定的順序,走過這棵樹所有的節點。 In-order : 先走左邊的子樹,再自己,再走右邊的子樹。 Pre-order :先自己,再走左邊的子樹,再走右邊的子樹。 Post-order : 先走左邊的子樹,再走右邊的子樹,再自己。 Level-order :同樣高度的先走,從左到右。 Tree Traversal Inorder Pre...
Figure 4. Subtrees and the binary search tree propertyFigure 5 shows two examples of binary trees. The one on the right, binary tree (b), is a BST because it exhibits the binary search tree property. Binary tree (a), however, is not a BST because not all nodes of the tree exhibit...