随笔分类 -  树

617. Merge Two Binary Trees
摘要：Given two binary trees and imagine that when you put one of them to cover the other, some nodes of the two trees are overlapped while the others are n 阅读全文
posted @ 2020-03-31 22:54 米开朗菠萝 阅读(94) 评论(0) 推荐(0)
257. Binary Tree Paths
摘要：Given a binary tree, return all root-to-leaf paths. Note: A leaf is a node with no children. Example: Input: 1 / \ 2 3 \ 5 Output: ["1->2->5", "1->3"] 阅读全文
posted @ 2020-03-12 05:11 米开朗菠萝 阅读(96) 评论(0) 推荐(0)
230. Kth Smallest Element in a BST
摘要：Given a binary search tree, write a function kthSmallest to find the kth smallest element in it. Note:You may assume k is always valid, 1 ≤ k ≤ BST's 阅读全文
posted @ 2020-03-12 04:48 米开朗菠萝 阅读(83) 评论(0) 推荐(0)
96. Unique Binary Search Trees
摘要：Given n, how many structurally unique BST's (binary search trees) that store values 1 ... n? Example: Input: 3 Output: 5 Explanation: Given n = 3, the 阅读全文
posted @ 2020-03-11 11:01 米开朗菠萝 阅读(114) 评论(0) 推荐(0)
515. Find Largest Value in Each Tree Row
摘要：You need to find the largest value in each row of a binary tree. Example: Input: 1 / \ 3 2 / \ \ 5 3 9 Output: [1, 3, 9] # Definition for a binary tre 阅读全文
posted @ 2020-03-10 20:22 米开朗菠萝 阅读(134) 评论(0) 推荐(0)
513. Find Bottom Left Tree Value
摘要：Given a binary tree, find the leftmost value in the last row of the tree. Example 1: Input: 2 / \ 1 3 Output: 1 Example 2: Input: 1 / \ 2 3 / / \ 4 5 阅读全文
posted @ 2020-03-10 20:10 米开朗菠萝 阅读(120) 评论(0) 推荐(0)
404. Sum of Left Leaves
摘要：Find the sum of all left leaves in a given binary tree. Example: 3 / \ 9 20 / \ 15 7 There are two left leaves in the binary tree, with values 9 and 1 阅读全文
posted @ 2020-03-10 19:41 米开朗菠萝 阅读(140) 评论(0) 推荐(0)
144. Binary Tree Preorder Traversal
摘要：Given a binary tree, return the preorder traversal of its nodes' values. Example: Input: [1,null,2,3] 1 \ 2 / 3 Output: [1,2,3] Follow up: Recursive s 阅读全文
posted @ 2020-03-08 11:05 米开朗菠萝 阅读(91) 评论(0) 推荐(0)
129. Sum Root to Leaf Numbers
摘要：Given a binary tree containing digits from 0-9 only, each root-to-leaf path could represent a number. An example is the root-to-leaf path 1->2->3 whic 阅读全文
posted @ 2020-03-08 10:53 米开朗菠萝 阅读(128) 评论(0) 推荐(0)
113. Path Sum II
摘要：Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum. Note: A leaf is a node with no children. Exampl 阅读全文
posted @ 2020-03-08 10:35 米开朗菠萝 阅读(125) 评论(0) 推荐(0)
114. Flatten Binary Tree to Linked List
摘要：Given a binary tree, flatten it to a linked list in-place. For example, given the following tree: 1 / \ 2 5 / \ \ 3 4 6 The flattened tree should look 阅读全文
posted @ 2020-03-07 16:07 米开朗菠萝 阅读(84) 评论(0) 推荐(0)
112. Path Sum
摘要：Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum. N 阅读全文
posted @ 2020-03-07 15:19 米开朗菠萝 阅读(145) 评论(0) 推荐(0)
100. Same Tree
摘要：Given two binary trees, write a function to check if they are the same or not. Two binary trees are considered the same if they are structurally ident 阅读全文
posted @ 2020-03-06 14:44 米开朗菠萝 阅读(117) 评论(0) 推荐(0)
226. Invert Binary Tree
摘要：Invert a binary tree. Example: Input: 4 / \ 2 7 / \ / \ 1 3 6 9 Output: 4 / \ 7 2 / \ / \ 9 6 3 1 # Definition for a binary tree node. # class TreeNod 阅读全文
posted @ 2020-03-01 16:02 米开朗菠萝 阅读(74) 评论(0) 推荐(0)
105. Construct Binary Tree from Preorder and Inorder Traversal
摘要：Given preorder and inorder traversal of a tree, construct the binary tree. Note:You may assume that duplicates do not exist in the tree. For example, 阅读全文
posted @ 2020-03-01 11:26 米开朗菠萝 阅读(133) 评论(0) 推荐(0)
102. Binary Tree Level Order Traversal
摘要：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 阅读全文
posted @ 2020-03-01 10:23 米开朗菠萝 阅读(136) 评论(0) 推荐(0)
94. Binary Tree Inorder Traversal
摘要：# Definition for a binary tree node. # class TreeNode(object): # def __init__(self, x): # self.val = x # self.left = None # self.right = None # 递归，中序遍 阅读全文
posted @ 2020-02-18 11:13 米开朗菠萝 阅读(88) 评论(0) 推荐(0)