ABC081_C Not so Diverse

mapの降順ソート(Value)

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Scanner;

public class MainC {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int k = sc.nextInt();
		int[] a = new int[n];
		for(int i = 0 ; i < n ; i++) a[i] = sc.nextInt();
		Map<Integer, Integer> map = new HashMap<>();
		for(int i = 0 ; i < n ; i++) {
			if(map.containsKey(a[i])) {
				map.put(a[i], map.get(a[i]) + 1);
			} else {
				map.put(a[i], 1);
			}
		}
		List<Entry<Integer, Integer>> entry = new ArrayList<>(map.entrySet());
		Collections.sort(entry, new Comparator<Entry<Integer, Integer>>() {
			public int compare(Entry<Integer, Integer> obj1, Entry<Integer, Integer> obj2) {
				return obj2.getValue() - obj1.getValue();
			}
		});
		int ans = 0;
		for(int i = k ; i < entry.size() ; i++) {
			ans += entry.get(i).getValue();
		}
		System.out.println(ans);
	}
}