给一个 二叉树 , 求最深节点的最小公共父节点 . retrun . 先用 recursive , 很快写出来了, 要求用 iterative . 时间不够了... Recursion: 返回的时候返回lca和depth,每个node如果有大于一个子节点的depth相同就返回这个node,如果有一个子节点depth更深就返回个子节点lca,这个o(n)就可以了 Iteration: tree的recursion换成iteration处理,一般用stack都能解决吧(相当于手动用stack模拟re…

June 8, 2015 我最喜欢的一道算法题目, 二行代码. 编程序需要很强的逻辑思维, 严密,我还没有很好训练自己．想一想, 二行代码, 五分钟就可以搞定; 最近这几天网上大家热议的 Homebrew 的作者 Max Howell 面试 Google 挂掉的一题, 二叉树反转, 七行代码, 相比二行代码, 情有可原!   One solution (Cannot pass the phone interview - need to improve, show reasoning, logic…

Given a binary tree rooted at root, the depth of each node is the shortest distance to the root. A node is deepest if it has the largest depth possible among any node in the entire tree. The subtree of a node is that node, plus the set of all descend…

Given a binary tree rooted at root, the depth of each node is the shortest distance to the root. A node is deepest if it has the largest depth possible among any node in the entire tree. The subtree of a node is that node, plus the set of all descend…

［抄题］: Given a binary tree rooted at root, the depth of each node is the shortest distance to the root. A node is deepest if it has the largest depth possible among any node in the entire tree. The subtree of a node is that node, plus the set of all d…

原题链接在这里:https://leetcode.com/problems/smallest-subtree-with-all-the-deepest-nodes/ 题目: Given a binary tree rooted at root, the depth of each node is the shortest distance to the root. A node is deepest if it has the largest depth possible among any n…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 日期 题目地址:https://leetcode.com/problems/smallest-subtree-with-all-the-deepest-nodes/description/ 题目描述 Given a binary tree rooted at root, the depth of each node is the shortest d…

Give a binary tree, elegantly print it so that no two tree nodes share the same column. Requirement: left child should appear on the left column of root, and right child should appear on the right of root. Example: a b c d e f z g h i j 这道题若能发现inorde…

The lowest common ancestor (LCA) of two nodes U and V in a tree is the deepest node that has both U and V as descendants. Given any two nodes in a binary tree, you are supposed to find their LCA. Input Specification: Each input file contains one test…

题目描述 The lowest common ancestor (LCA) of two nodes U and V in a tree is the deepest node that has both U and V as descendants.Given any two nodes in a binary tree, you are supposed to find their LCA. 最小共同祖先(LCA)是一棵树中两个节点U和V最深的那个公共父节点.要求给一棵树,以及两个节点,请你…