迷宫

迷宫 - 蓝桥云课 (lanqiao.cn)

public class N602 {
	static char[][] m = new char[30][50];
	static char[] d = { 'D', 'L', 'R', 'U' };// 定义这个顺序为字典序答案就是最小字典序
	static int[][] dir = { { 1, 0 }, { 0, -1 }, { 0, 1 }, { -1, 0 } };// 方向数组的序号与上面的对应

	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		for (int i = 0; i < 30; i++) {// 输入
			String s = scanner.next();
			for (int j = 0; j < 50; j++) {
				m[i][j] = s.charAt(j);
			}
		}
		bfs();// 广搜
	}

	static void bfs() {
		LinkedList<Node> q = new LinkedList<>();// 定义一个队列
		m[0][0] = '1';// 广搜仅走一次
		q.addLast(new Node(0, 0));// 第一个节点入队
		while (!q.isEmpty()) {
			Node next, now;
			now = q.removeFirst();
			if (now.x == 29 && now.y == 49) {
				System.out.println(now.s);
			}
			for (int i = 0; i < 4; i++) {
				next = new Node(now.x + dir[i][0], now.y + dir[i][1]);
				if (next.x >= 0 && next.x <= 29 && next.y >= 0 && next.y <= 49 && m[next.x][next.y] == '0') {// 符合条件入队
					next.s = now.s + d[i];// 字符串拼接
					q.addLast(next);
					m[next.x][next.y] = '1';
				}
			}
		}
	}
}

class Node {
	int x;
	int y;
	String s;

	public Node(int x, int y) {
		this.x = x;
		this.y = y;
		this.s = "";
	}
}