forked from krish-ag/HacktoberFest22-Repo-DSA
-
Notifications
You must be signed in to change notification settings - Fork 0
/
topKFrequentElements.java
49 lines (31 loc) · 1.09 KB
/
topKFrequentElements.java
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
import java.util.HashMap;
import java.util.Map;
import java.util.PriorityQueue;
import java.util.Scanner;
public class topKFrequentElements {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int n = sc.nextInt();
int arr[] = new int[n];
for (int i = 0; i < n; i++)
arr[i] = sc.nextInt();
int k = sc.nextInt();
int ans[] = new int[k];
ans = topKFrequent(arr, k);
for (int i = 0; i < k; i++)
System.out.print(ans[i] + " ");
}
public static int[] topKFrequent(int[] nums, int k) {
HashMap<Integer, Integer> map = new HashMap<>();
for (int i : nums)
map.put(i, map.getOrDefault(i, 0) + 1);
PriorityQueue<Map.Entry<Integer, Integer>> pq = new PriorityQueue<>((a, b) -> b.getValue() - a.getValue());
for (Map.Entry<Integer, Integer> i : map.entrySet()) {
pq.add(i);
}
int ans[] = new int[k];
for (int i = 0; i < k; i++)
ans[i] = pq.remove().getKey();
return ans;
}
}