{ "data": { "question": { "questionId": "1470", "questionFrontendId": "1348", "boundTopicId": null, "title": "Tweet Counts Per Frequency", "titleSlug": "tweet-counts-per-frequency", "content": "
A social media company is trying to monitor activity on their site by analyzing the number of tweets that occur in select periods of time. These periods can be partitioned into smaller time chunks based on a certain frequency (every minute, hour, or day).
\n\nFor example, the period [10, 10000] (in seconds) would be partitioned into the following time chunks with these frequencies:
[10,69], [70,129], [130,189], ..., [9970,10000][10,3609], [3610,7209], [7210,10000][10,10000]Notice that the last chunk may be shorter than the specified frequency's chunk size and will always end with the end time of the period (10000 in the above example).
Design and implement an API to help the company with their analysis.
\n\nImplement the TweetCounts class:
TweetCounts() Initializes the TweetCounts object.void recordTweet(String tweetName, int time) Stores the tweetName at the recorded time (in seconds).List<Integer> getTweetCountsPerFrequency(String freq, String tweetName, int startTime, int endTime) Returns a list of integers representing the number of tweets with tweetName in each time chunk for the given period of time [startTime, endTime] (in seconds) and frequency freq.\n\tfreq is one of "minute", "hour", or "day" representing a frequency of every minute, hour, or day respectively.\n
Example:
\n\n\nInput\n["TweetCounts","recordTweet","recordTweet","recordTweet","getTweetCountsPerFrequency","getTweetCountsPerFrequency","recordTweet","getTweetCountsPerFrequency"]\n[[],["tweet3",0],["tweet3",60],["tweet3",10],["minute","tweet3",0,59],["minute","tweet3",0,60],["tweet3",120],["hour","tweet3",0,210]]\n\nOutput\n[null,null,null,null,[2],[2,1],null,[4]]\n\nExplanation\nTweetCounts tweetCounts = new TweetCounts();\ntweetCounts.recordTweet("tweet3", 0); // New tweet "tweet3" at time 0\ntweetCounts.recordTweet("tweet3", 60); // New tweet "tweet3" at time 60\ntweetCounts.recordTweet("tweet3", 10); // New tweet "tweet3" at time 10\ntweetCounts.getTweetCountsPerFrequency("minute", "tweet3", 0, 59); // return [2]; chunk [0,59] had 2 tweets\ntweetCounts.getTweetCountsPerFrequency("minute", "tweet3", 0, 60); // return [2,1]; chunk [0,59] had 2 tweets, chunk [60,60] had 1 tweet\ntweetCounts.recordTweet("tweet3", 120); // New tweet "tweet3" at time 120\ntweetCounts.getTweetCountsPerFrequency("hour", "tweet3", 0, 210); // return [4]; chunk [0,210] had 4 tweets\n\n\n\n
Constraints:
\n\n0 <= time, startTime, endTime <= 1090 <= endTime - startTime <= 104104 calls in total to recordTweet and getTweetCountsPerFrequency.Compiled with clang 11 using the latest C++ 17 standard.
Your code is compiled with level two optimization (-O2). AddressSanitizer is also enabled to help detect out-of-bounds and use-after-free bugs.
Most standard library headers are already included automatically for your convenience.
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