Note: For the coding companion problem, please see: Encode and Decode TinyURL. How would you design a URL shortening service that is similar to TinyURL? Background:TinyURL is a URL shortening service where you enter a URL such as https://leetcode.com…

原题链接在这里:https://leetcode.com/problems/design-tinyurl/description/ 题目: How would you design a URL shortening service that is similar to TinyURL? Background:TinyURL is a URL shortening service where you enter a URL such as https://leetcode.com/problems…

Note: For the coding companion problem, please see: Encode and Decode TinyURL. How would you design a URL shortening service that is similar to TinyURL? Background:TinyURL is a URL shortening service where you enter a URL such as https://leetcode.com…

Design a Phone Directory which supports the following operations: get: Provide a number which is not assigned to anyone. check: Check if a number is available or not. release: Recycle or release a number. Example: // Init a phone directory containing…

Design a hit counter which counts the number of hits received in the past 5 minutes. Each function accepts a timestamp parameter (in seconds granularity) and you may assume that calls are being made to the system in chronological order (ie, the times…

Design a simplified version of Twitter where users can post tweets, follow/unfollow another user and is able to see the 10 most recent tweets in the user's news feed. Your design should support the following methods: postTweet(userId, tweetId): Compo…

Design a Snake game that is played on a device with screen size = width x height. Play the game online if you are not familiar with the game. The snake is initially positioned at the top left corner (0,0) with length = 1 unit. You are given a list of…

Design a Tic-tac-toe game that is played between two players on a n x n grid. You may assume the following rules: A move is guaranteed to be valid and is placed on an empty block.Once a winning condition is reached, no more moves is allowed.A player…

原题链接在这里:https://leetcode.com/problems/design-hit-counter/. 题目: Design a hit counter which counts the number of hits received in the past 5 minutes. Each function accepts a timestamp parameter (in seconds granularity) and you may assume that calls are…

Design a search autocomplete system for a search engine. Users may input a sentence (at least one word and end with a special character '#'). For each character they type except '#', you need to return the top 3historical hot sentences that have pref…