240730 레이저 통신

static class Point {
	int x;
	int y;
	int direction;

	Point(int x, int y, int direction) {
		this.x = x;
		this.y = y;
		this.direction = direction;
	}
}

public static void main(String[] args) throws IOException {
	BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
	String[] input = br.readLine().split(" ");
	int height = Integer.parseInt(input[0]);
	int width = Integer.parseInt(input[1]);
	char[][] map = new char[width][height];
	int startX1 = -1;
	int startY1 = -1;
	int startX2 = -1;
	int startY2 = -1;

	for (int i = 0; i < width; i++) {
		String line = br.readLine();
		for (int j = 0; j < height; j++) {
			map[i][j] = line.charAt(j);
			if (map[i][j] == 'C') {
				if (startX1 == -1) {
					startX1 = i;
					startY1 = j;
				} else {
					startX2 = i;
					startY2 = j;
				}
				map[i][j] = '.';
			}
		}
	}

	int[][] check = new int[width][height];
	Deque<Point> queue = new LinkedList<>();
	int[] dx = { -1, 1, 0, 0 };
	int[] dy = { 0, 0, -1, 1 };
	check[startX1][startY1] = 1;
	queue.add(new Point(startX1, startY1, -1));

	while (!queue.isEmpty()) {
		Point current = queue.poll();

		for (int i = 0; i < 4; i++) {
			if (current.direction == i)
				continue;

			int nx = current.x;
			int ny = current.y;
			int count = check[current.x][current.y] + 1;

			while (true) {
				nx += dx[i];
				ny += dy[i];

				if (nx < 0 || nx >= width || ny < 0 || ny >= height || map[nx][ny] != '.')
					break;

				if (check[nx][ny] == 0) {
					queue.add(new Point(nx, ny, i));
					check[nx][ny] = count;
				}

				if (check[nx][ny] != 0 && check[nx][ny] < count)
					break;
			}
		}
	}

	System.out.println(check[startX2][startY2] - 2);
}

출처:https://www.acmicpc.net/problem/6087