wangjikun123的博客

问题描述Given a string, sort it in decreasing order based on the frequency of characters.给定一个字符串，请将字符串里的字符按照出现的频率降序排列。思路使用hashtable遍历字符串，将出现频率记录在hashtable中，最后利用hashtable对原字符串进行排序class Solution {public: string frequencySort(string s) {

问题描述Design a data structure that follows the constraints of a LeastRecently Used (LRU) cache.Implement the LRUCache class:LRUCache(int capacity) Initialize the LRU cache with positive size capacity.int get(int key) Return the value of the key if

问题描述Design a data structure that is initialized with a list of differentwords. Provided a string, you should determine if you can changeexactly one character in this string to match any word in the datastructure. Implement the MagicDictionary class:

问题描述Given a non-empty string s and a dictionary wordDict containing a listof non-empty words, determine if s can be segmented into aspace-separated sequence of one or more dictionary words.Note:The same word in the dictionary may be reused multiple

问题描述Given head, the head of a linked list, determine if the linked list has a cycle in it.There is a cycle in a linked list if there is some node in the list that can be reached again by continuously following the next pointer. Internally, pos is used t

问题描述Given an array of integers nums and an integer target, return indicesof the two numbers such that they add up to target.You may assume that each input would have exactly one solution, andyou may not use the same element twice.You can return the a

题目内容Given an array of integers, return indices of the two numbers such that they add up to a specific target. You may assume that each input would have exactly one solution, and you may not use the sam

121.买卖股票的最佳时间 I题目内容给定一个数组，它的第 i 个元素是一支给定股票第 i 天的价格。 如果你最多只允许完成一笔交易（即买入和卖出一支股票），设计一个算法来计算你所能获取的最大利润。 注意你不能在买入股票前卖出股票。思路引入两个变量，最小买入价格和最大利润，遍历数组，判断最大和最小值来得到最后的结果。代码class Solution: def maxProfit(self