玩家控制两只企鹅分别在两张 20×20 的地图上行动。地图上有一些格子是墙壁,无法到达。当控制企鹅向墙壁或者边界移动时,这个操作会被忽略。
现在同时控制两只企鹅移动,不过企鹅的移动是镜像的:
L :左边的企鹅向左移动,右边的企鹅向右移动;
R :左边的企鹅向右移动,右边的企鹅向左移动;
U :两只企鹅均向上移动;
D :两只企鹅均向下移动;
左边企鹅从 (20,20) 出发前往 (1,20) ,右边企鹅从 (20,1) 出发前往 (1,1) ,求最短操作序列。若有多组解,求字典序最小的解(D<L<R<U)。
注意:当一只企鹅到达目的地而另一只没有到达时,已经到达目的地的企鹅可能仍会离开目的地。
27
LULLUURRUUUUUUULUUUUURRUUUU
#..................A A............##...#.
...................A A......#.....#.....#
.........#...#.#...A A..#....#...........
#........#.........A A..#..#.............
........#......#.AAA AA#.#......#.#.....#
......#.#..#.#...A#. .A.....##.....##...#
....#...........#A.# .A..................
.##..............A.. .A.........#..#...#.
.....#.#........#A#. #A........#.#.......
.................AA. AA#....#..........#.
....#.#..........#A. A#.........#..#..#..
.........#.......#A. A.#.................
...#..#......#...#A. A.....#.............
...........#...#..A. A...................
..##..#.#....#..#.A. A.............#...#.
.#..#...#.#.....##A. A........#.#...#....
.#.........#....AAA. AAA...........#.#...
..##.#........#.A.#. ##A.................
....##.#........AAA. AAA....#.....#......
..........##......AA A#..#.#...........#.