230617 압축

public int[] solution(String msg) {
	List<Integer> list = new ArrayList<>();
	int num = 1;
	Map<String, Integer> map = new HashMap<>();

	for (int i = 65; i <= 90; i++) {
		String c = String.valueOf((char) i);
		map.put(c, num++);
	}

	for (int i = 0; i < msg.length();) {
		int j = msg.length() - i;
		while (!map.containsKey(msg.substring(i, i + j))) {
			j--;
			if (j == 0) {
				break;
			}
		}
		String s = msg.substring(i, i + j);

		if (i + j == msg.length()) {
			list.add(map.get(s));
		} else {
			s = msg.substring(i, i + j + 1);
			list.add(map.get(s.substring(0, s.length() - 1)));
		}
		map.put(s, num++);
		i += j;
	}

	int[] answer = new int[list.size()];
	for (int i = 0; i < answer.length; i++) {
		answer[i] = list.get(i);
	}

	return answer;
}

출처:https://school.programmers.co.kr/learn/courses/30/lessons/17684