package Leetcode;

import java.util.*;

public class TopKFrequentWords {

public static List<String> topKFrequent(String[] words, int k) {

Map<String, Integer> wordFrequency = new HashMap<>();

PriorityQueue<String> pq = new PriorityQueue<>((word1, word2) ->

wordFrequency.get(word1).equals(wordFrequency.get(word2)) ?

word2.compareTo(word1) : wordFrequency.get(word1) - wordFrequency.get(word2));

List<String> result = new ArrayList<>();

for(String word : words) {

wordFrequency.put(word, wordFrequency.getOrDefault(word, 0) + 1);

}

for(String word : wordFrequency.keySet()) {

pq.offer(word);

if(pq.size() > k)

pq.poll();

}

while(!pq.isEmpty()) {

result.add(0, pq.poll());

}

return result;

}

public static void main(String[] args) {

String[] arr = new String[]{"i", "love", "leetcode", "i", "love", "coding"};

System.out.println(topKFrequent(arr, 2));

}

}