leetcode 235-290 easy】的更多相关文章

Given a binary search tree (BST), find the lowest common ancestor (LCA) of two given nodes in the BST. According to the definition of LCA on Wikipedia: “The lowest common ancestor is defined between two nodes v and w as the lowest node in T that has…
Given a binary search tree (BST), find the lowest common ancestor (LCA) of two given nodes in the BST. According to the definition of LCA on Wikipedia: “The lowest common ancestor is defined between two nodes p and q as the lowest node in T that has…
235. 二叉搜索树的最近公共祖先 235. Lowest Common Ancestor of a Binary Search Tree 题目描述 给定一个二叉搜索树,找到该树中两个指定节点的最近公共祖先. 百度百科中最近公共祖先的定义为: "对于有根树 T 的两个结点 p.q,最近公共祖先表示为一个结点 x,满足 x 是 p.q 的祖先且 x 的深度尽可能大(一个节点也可以是它自己的祖先)." 例如,给定如下二叉搜索树: root = [6,2,8,0,4,7,9,null,nul…
235. 二叉搜索树的最近公共祖先 题目描述 给定一个二叉搜索树, 找到该树中两个指定节点的最近公共祖先. 百度百科中最近公共祖先的定义为:"对于有根树 T 的两个结点 p.q,最近公共祖先表示为一个结点 x,满足 x 是 p.q 的祖先且 x 的深度尽可能大(一个节点也可以是它自己的祖先)." 示例 例如,给定如下二叉搜索树: root = [6,2,8,0,4,7,9,null,null,3,5] 示例 1: 输入: root = [6,2,8,0,4,7,9,null,null,…
Given a binary search tree (BST), find the lowest common ancestor (LCA) of two given nodes in the BST. According to the definition of LCA on Wikipedia: “The lowest common ancestor is defined between two nodes v and w as the lowest node in T that has…
一天一道LeetCode 本系列文章已全部上传至我的github,地址:ZeeCoder's Github 欢迎大家关注我的新浪微博,我的新浪微博 欢迎转载,转载请注明出处 (一)题目 Given a pattern and a string str, find if str follows the same pattern. Here follow means a full match, such that there is a bijection between a letter in pa…
https://www.cnblogs.com/grandyang/p/4641968.html http://www.cnblogs.com/grandyang/p/4640572.html 利用二叉搜索树的性质:左子树所有节点小于根节点,右子树所有节点大于根节点 如果两个节点的最大值小于根节点,那最低公共祖先一定在左子树,去左子树找: 如果两个节点的最小值大于根节点,那最低公共祖先一定在右子树,去右子树找: 其他情况下,当前节点一定就是最低公共祖先.其中,其他情况包括两种,即p是q或者q是p…
problem 290. Word Pattern 多理解理解题意!!! 不过博主还是不理解,应该比较的是单词的首字母和pattern的顺序是否一致.疑惑!知道的可以分享一下下哈- 之前理解有误,应该是pattern中的每个字符和某个单词的一一映射关系. class Solution { public: bool wordPattern(string pattern, string str) { map<char, int> p2i; map<string, int> s2i; ;…
描述: 给定二叉树两个节点,求其最近公共祖先.最近即所有公共祖先中深度最深的. ps:自身也算自身的祖先. 235题解决: 这是二叉搜索树,有序的,左边小右边大. TreeNode* lowestCommonAncestor(TreeNode* root, TreeNode* p, TreeNode* q) { if (root == NULL || root == p || root == q) return root; if ((root->val > p->val &&am…
Implement atoi to convert a string to an integer. Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possible input cases. Notes: It is intended for this problem to be spe…