230628 귤 고르기

public int solution(int k, int[] tangerine) {
	Map<Integer, Integer> sizeMap = new HashMap<>();

	for (int size : tangerine) {
		sizeMap.put(size, sizeMap.getOrDefault(size, 0) + 1);
	}

	List<Integer> keyList = new ArrayList<>(sizeMap.keySet());
	keyList.sort(Comparator.comparingInt(sizeMap::get).reversed());

	int answer = 0;
	for (int i = 0; i < keyList.size() && k > 0; i++) {
		int size = keyList.get(i);
		int count = sizeMap.get(size);
		answer++;
		k -= count;
	}

	return answer;
}

출처:https://school.programmers.co.kr/learn/courses/30/lessons/138476