Given a binary tree, flatten it to a linked list in-place. (Medium) For example,Given 1 / \ 2 5 / \ \ 3 4 6 The flattened tree should look like: 1 \ 2 \ 3 \ 4 \ 5 \ 6 分析: 将树的问题和链表插入问题结合.对于每个节点,寻找左子树的最右端,它应该是左子树前序遍历的最后一位,也就是生成链表中,右子树根节点的前一位. 按照链表插入的方法…

给定一个二叉树,原地将它展开为链表. 例如,给定二叉树 1 / \ 2 5 / \ \ 3 4 6 将其展开为: 1 \ 2 \ 3 \ 4 \ 5 \ 6 class Solution { public: TreeNode *last = NULL; void flatten(TreeNode* root) { if(root == NULL) return; TreeNode *r = root ->right; if(last != NULL) { last ->right = root…

Flatten a binary tree to a fake "linked list" in pre-order traversal. Here we use the right pointer in TreeNode as the next pointer in ListNode. Notice Don't forget to mark the left child of each node to null. Or you will get Time Limit Exceeded…

Flatten Binary Tree to Linked List Given a binary tree, flatten it to a linked list in-place. For example, Given 1 / \ 2 5 / \ \ 3 4 6 The flattened tree should look like: 1 \ 2 \ 3 \ 4 \ 5 \ 6 click to show hints. Hints: If you notice carefully in t…

114. Flatten Binary Tree to Linked List (Medium) 453. Flatten Binary Tree to Linked List (Easy) 解法1: 用stack. class Solution { public: void flatten(TreeNode *root) { if(!root) return; TreeNode *pnode = NULL; stack<TreeNode*> s; s.push(root); while(!s…

随笔一记,留做重温! Flatten Binary Tree to Linked List Given a binary tree, flatten it to a linked list in-place. For example, Given 1 / \ 2 5 / \ \ 3 4 6 The flattened tree should look like: 1 \ 2 \ 3 \ 4 \ 5 \ 6 第一个想法是先序遍历,然后按照访问顺序,添加右结点. public static void…

. Flatten Binary Tree to Linked List Given a binary tree, flatten it to a linked list in-place. For example, given the following tree: / \ / \ \ The flattened tree should look like: \ \ \ \ \ /** * Definition for a binary tree node. * struct TreeNode…

题目 给定一个二叉树,原地将它展开为链表. 例如,给定二叉树 1 / \ 2 5 / \ \ 3 4 6 将其展开为: 1 \ 2 \ 3 \ 4 \ 5 \ 6 解析 通过递归实现:可以用先序遍历,然后串成链表 主要思想就是:先递归对右子树进行链表化并记录,然后将root->right指向 左子树进行链表化后的头结点,然后一直向右遍历子树,连接上之前的右子树 /** * Definition for a binary tree node. * struct TreeNode { * int v…

Flatten Binary Tree to Linked List Given a binary tree, flatten it to a linked list in-place. For example,Given 1 / \ 2 5 / \ \ 3 4 6 The flattened tree should look like: 1 \ 2 \ 3 \ 4 \ 5 \ 6 SOLUTION 1:使用递归解决,根据left是否为空,先连接left tree, 然后再连接右子树.使用一个t…

Flatten Binary Tree to Linked List: Given a binary tree, flatten it to a linked list in-place. For example, Given 1 / \ 2 5 / \ \ 3 4 6 The flattened tree should look like: 1 \ 2 \ 3 \ 4 \ 5 \ 6 这题的主要难点是"in-place".因为这个flatten的顺序是中.左.右(相当于中序遍历),所…