Top K Frequent Elements - Hashing Problem

Problem : Get top K frequent elements.

Implementation:

	package hashTables.problems;
	import java.util.ArrayList;
	import java.util.LinkedHashMap;
	import java.util.Map;
	public class TopKFrequentEles {
	static ArrayList<Integer> TopK(int[] arr, int k) {
	//int[] arr = array.stream().mapToInt(i->i).toArray();
	int l1 = arr.length;
	Map<Integer, Integer> countMap = new LinkedHashMap<>();
	for (int i = 0; i < l1; i++) {
	if (countMap.containsKey(arr[i])) {
	countMap.put(arr[i], countMap.get(arr[i]) + 1);
	} else {
	countMap.put(arr[i], 1);
	}
	}
	ArrayList<Integer> result = new ArrayList<Integer>();
	countMap.entrySet().stream().sorted(Map.Entry.<Integer, Integer>comparingByValue().reversed().thenComparing(Map.Entry.<Integer, Integer>comparingByKey().reversed())).forEach(e -> {
	int key = e.getKey();
	int val = e.getValue();
	for (int i = 0; i < val; i++) {
	if(!result.contains(key) && result.size()<k)
	result.add(key);
	else
	break;
	}
	});
	return result;
	}
	public static void main(String[] args) {
	int arr2[]= {8,1,1,2,2,3,3,3,4};
	ArrayList<Integer> result = TopK(arr2,2);
	for(int i: result) {
	System.out.println(i);
	}
	}
	}

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