Package g1301_1400.s1348_tweet_counts_per_frequency

Class TweetCounts

java.lang.Object
g1301_1400.s1348_tweet_counts_per_frequency.TweetCounts
public class TweetCounts extends java.lang.Object
1348 - Tweet Counts Per Frequency.

Medium

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 ).

For example, the period [10, 10000] (in seconds ) would be partitioned into the following time chunks with these frequencies:

  • Every minute (60-second chunks): [10,69], [70,129], [130,189], ..., [9970,10000]
  • Every hour (3600-second chunks): [10,3609], [3610,7209], [7210,10000]
  • Every day (86400-second chunks): [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.

Implement 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.
    • freq is one of "minute", "hour", or "day" representing a frequency of every minute , hour , or day respectively.

Example:

Input [“TweetCounts”,“recordTweet”,“recordTweet”,“recordTweet”,“getTweetCountsPerFrequency”,“getTweetCountsPerFrequency”,“recordTweet”,“getTweetCountsPerFrequency”]

[ [],[“tweet3”,0],[“tweet3”,60],[“tweet3”,10],[“minute”,“tweet3”,0,59],[“minute”,“tweet3”,0,60],[“tweet3”,120],[“hour”,“tweet3”,0,210]]

Output: [null,null,null,null,[2],[2,1],null,[4]]

Explanation:

TweetCounts tweetCounts = new TweetCounts();

tweetCounts.recordTweet(“tweet3”, 0); // New tweet “tweet3” at time 0

tweetCounts.recordTweet(“tweet3”, 60); // New tweet “tweet3” at time 60

tweetCounts.recordTweet(“tweet3”, 10); // New tweet “tweet3” at time 10

tweetCounts.getTweetCountsPerFrequency(“minute”, “tweet3”, 0, 59); // return [2]; chunk [0,59] had 2 tweets

tweetCounts.getTweetCountsPerFrequency(“minute”, “tweet3”, 0, 60); // return [2,1]; chunk [0,59] had 2 tweets, chunk [60,60] had 1 tweet

tweetCounts.recordTweet(“tweet3”, 120); // New tweet “tweet3” at time 120

tweetCounts.getTweetCountsPerFrequency(“hour”, “tweet3”, 0, 210); // return [4]; chunk [0,210] had 4 tweets

Constraints:

  • 0 <= time, startTime, endTime <= 109
  • 0 <= endTime - startTime <= 104
  • There will be at most 104 calls in total to recordTweet and getTweetCountsPerFrequency.

  • Constructor Summary

    Constructors
    Constructor
    Description
    TweetCounts()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    java.util.List<java.lang.Integer>
    getTweetCountsPerFrequency(java.lang.String freq, java.lang.String tweetName, int startTime, int endTime)
     
    void
    recordTweet(java.lang.String tweetName, int time)
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • TweetCounts

      public TweetCounts()

  • Method Details

    • recordTweet

      public void recordTweet(java.lang.String tweetName, int time)

    • getTweetCountsPerFrequency

      public java.util.List<java.lang.Integer> getTweetCountsPerFrequency(java.lang.String freq, java.lang.String tweetName, int startTime, int endTime)