231026 호텔 대실

public int solution(String[][] bookTimeSlots) {
	int[] roomUsage = new int[1449];
	for (String[] timeSlot : bookTimeSlots) {
		int startTime = convertToMinutes(timeSlot[0]);
		int endTime = convertToMinutes(timeSlot[1]) + 9;
		incrementRoomUsage(roomUsage, startTime, endTime);
	}

	return maxRoomUsage(roomUsage);
}

public int convertToMinutes(String time) {
	int hours = Integer.parseInt(time.substring(0, 2));
	int minutes = Integer.parseInt(time.substring(3, 5));
	return (hours * 60) + minutes;
}

public void incrementRoomUsage(int[] roomUsage, int startTime, int endTime) {
	for (int i = startTime; i <= endTime; i++) {
		roomUsage[i]++;
	}
}

public int maxRoomUsage(int[] roomUsage) {
	return Arrays.stream(roomUsage).max().getAsInt();
}

출처:https://school.programmers.co.kr/learn/courses/30/lessons/155651