今天发现LintCode页面刷新不出来了,所以就转战LeetCode.还是像以前一样,做题顺序:难度从低到高,每天至少一题. 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 pattern and a non-empty word in …

Given a binary search tree (BST) with duplicates, find all the mode(s) (the most frequently occurred element) in the given BST. Assume a BST is defined as follows: The left subtree of a node contains only nodes with keys less than or equal to the nod…

Given a 32-bit signed integer, reverse digits of an integer. Example 1: Input: 123 Output: 321 Example 2: Input: -123 Output: -321 Example 3: Input: 120 Output: 21 Note:Assume we are dealing with an environment which could only store integers within…

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; ;…

290. Word Pattern istringstream 是将字符串变成字符串迭代器一样,将字符串流在依次拿出,比较好的是,它不会将空格作为流,这样就实现了字符串的空格切割. C++引入了ostringstream.istringstream.stringstream这三个类,要使用他们创建对象就必须包含sstream.h头文件. istringstream类用于执行C++风格的串流的输入操作. ostringstream类用于执行C风格的串流的输出操作. strstream类同时可以支持…

Description Given a collection of intervals, merge all overlapping intervals. Example Given intervals => merged intervals: [ [ (1, 3), (1, 6), (2, 6), => (8, 10), (8, 10), (15, 18) (15, 18) ] ] Challenge O(n log n) time and O(1) extra space. 题意:给定一个…

[leetcode 字符串处理]Compare Version Numbers @author:wepon @blog:http://blog.csdn.net/u012162613 1.题目 Compare two version numbers version1 and version1. If version1 > version2 return 1, if version1 < version2 return -1, otherwise return 0. You may assume…

LeetCode第27题 Given an array nums and a value val, remove all instances of that value in-place and return the new length. Do not allocate extra space for another array, you must do this by modifying the input array in-place with O(1) extra memory. The…

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 pattern and a non-empty word in str. Example 1: Input: pattern = "abba", str = "dog c…

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 pattern and a non-empty word in str. Example 1: Input: pattern = "abba", str = "dog c…