240220 방문 길이

public int solution(String dirs) {
	Set<String> set = new HashSet<>();
	int[][] pos = new int[1][2];
	pos[0][0] = 0;
	pos[0][1] = 0;

	for (char direction : dirs.toCharArray()) {
		int[][] tempPos = new int[1][2];
		tempPos[0][0] = pos[0][0];
		tempPos[0][1] = pos[0][1];

		move(tempPos, direction);

		if (isValidMove(tempPos[0])) {
			String path1 = posToString(pos[0]) + posToString(tempPos[0]);
			String path2 = posToString(tempPos[0]) + posToString(pos[0]);

			set.add(path1);
			set.add(path2);

			pos[0][0] = tempPos[0][0];
			pos[0][1] = tempPos[0][1];
		}
	}

	return set.size() / 2;
}

private void move(int[][] pos, char direction) {
	switch (direction) {
		case 'U':
			pos[0][1]++;
			break;
		case 'D':
			pos[0][1]--;
			break;
		case 'R':
			pos[0][0]++;
			break;
		case 'L':
			pos[0][0]--;
			break;
		default:
			break;
	}
}

private boolean isValidMove(int[] pos) {
	return pos[0] >= -5 && pos[0] <= 5 && pos[1] >= -5 && pos[1] <= 5;
}

private String posToString(int[] pos) {
	return pos[0] + "," + pos[1];
}

출처:https://school.programmers.co.kr/learn/courses/30/lessons/49994