acdream 1043 Always Turn Left（模拟）

题目链接

Always Turn Left

Time Limit: 2000/1000MS (Java/Others) Memory Limit: 128000/64000KB (Java/Others)

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Problem Description

You find yourself standing outside of a perfect maze. A maze is defined as "perfect" if it meets the following conditions:

• It is a rectangular grid of rooms, R rows by C columns.
• There are exactly two openings on the outside of the maze: the entrance and the exit.
• The entrance is always on the north wall, while the exit could be on any wall.
• There is exactly one path between any two rooms in the maze (that is, exactly one path that does not involve backtracking).

You decide to solve the perfect maze using the "always turn left" algorithm, which states that you take the leftmost fork at every opportunity.

If you hit a dead end, you turn right twice (180 degrees clockwise) and continue. (If you were to stick out your left arm and touch the wall while following this algorithm, you'd solve the maze without ever breaking contact with the wall.)

Once you finish the maze, you decide to go the extra step and solve it again (still always turning left), but starting at the exit and finishing at the entrance.

The path you take through the maze can be described with three characters: 'W' means to walk forward into the next room, 'L' means to turn left (or counterclockwise) 90 degrees, and 'R' means to turn right (or clockwise) 90 degrees.

You begin outside the maze, immediately adjacent to the entrance, facing the maze.

You finish when you have stepped outside the maze through the exit.

For example, if the entrance is on the north and the exit is on the west, your path through the following maze would beWRWWLWWLWWLWLWRRWRWWWRWWRWLW:

If the entrance and exit were reversed such that you began outside the west wall and finished out the north wall, your path would beWWRRWLWLWWLWWLWWRWWRWWLW.

Given your two paths through the maze (entrance to exit and exit to entrance), your code should return a description of the maze.

Input

The first line of input gives the number of cases, N.

N test cases follow. Each case is a line formatted as:

"entrance_to_exit exit_to_entrance"

1 ≤ N ≤ 100.

2 ≤ len(entrance_to_exit) ≤ 10000.

2 ≤ len(exit_to_entrance) ≤ 10000.

Output

You can assume that the size(row or column) of the maze will not lager than 100.

All paths will be at least two characters long, consist only of the characters 'W', 'L', and 'R', and begin and end with 'W'.

For each test case, output one line containing "Case #x:" by itself. The next R lines give a description of the R by C maze.

There should be C characters in each line, representing which directions it is possible to walk from that room. Refer to the following legend:

Character Can walk north? Can walk south? Can walk west? Can walk east?

Character	Can walk north?	Can walk south?	Can walk west?	Can walk east?
1	Yes	No	No	No
2	No	Yes	No	No
3	Yes	Yes	No	No
4	No	No	Yes	No
5	Yes	No	Yes	No
6	No	Yes	Yes	No
7	Yes	Yes	Yes	No
8	No	No	No	Yes
9	Yes	No	No	Yes
a	No	Yes	No	Yes
b	Yes	Yes	No	Yes
c	No	No	Yes	Yes
d	Yes	No	Yes	Yes
e	No	Yes	Yes	Yes
f	Yes	Yes	Yes	Yes

Sample Input

3
WRWWLWWLWWLWLWRRWRWWWRWWRWLW WWRRWLWLWWLWWLWWRWWRWWLW
WW WW
WLW WWRRWLW

Sample Output

Case #1:
ac5
386
9c7
e43
9c5
Case #2:
3
Case #3:
8d

题意：有一个N*M的迷宫，只有一个入口，一个出口，一个人从出口开始走迷宫，假设遇到路口优先左转，假设走到死胡同右转两次。入口一定在北方。告诉你那个人从入口走到出口，又从出口走到入口的走法。分别是两个字符串，‘W'表示前进，'L'表示左转，’R’表示右转。现在让你构造出这个迷宫。

题解：初看题感觉无从下手，走法不一定把每个格子走完，怎么能构造出迷宫。但是，既然题目让你构造出这个迷宫，说明数据保证一定能走到每个格子。那么不管三七二十一，直接模拟就是了。当走到一个格子的时候，如果没有左转说明不能向左走，如果既没有左转又没有直走，说明那两个方向都不能走。用两个字符串模拟两遍，就能确定出每个格子的状态了。