题目描述
A monocycle is a cycle that runs on one wheel. We will be considering a special one which has a solid wheel colored with five different colors as shown in the figure:
The colored segments make equal angles (72o) at the center. A monocyclist rides this cycle on an M x N grid of square tiles. The tiles are of a size such that moving forward from the center of one tile to that of the next one makes the wheel rotate exactly 72o around its center. The effect is shown in the above figure. When the wheel is at the center of square 1, the midpoint of its blue segment is in touch with the ground. But when the wheel moves forward to the center of the next square (square 2) the midpoint of its white segment touches the ground.
Some of the squares of the grid are blocked and hence the cyclist cannot move to them. The cyclist starts from some square and tries to move to a target square in minimum amount of time. From any square he either moves forward to the next square or he remains in the same square but turns 90o left or right. Each of these actions requires exactly 1 second to execute. He always starts his ride facing north and with the midpoint of the green segment of his wheel touching the ground. In the target square, too, the green segment must touch the ground but he does not care which direction he will be facing.
Please help the monocyclist check whether the destination is reachable and if so the minimum amount of time he will require to reach it.
输入
The input may contain multiple test cases.
The first line of each test case contains two integers M and N (1<=M, N<=25) giving the dimensions of the grid. Then follows the description of the grid in M lines of N characters each. The character “#'' will indicate a blocked square, but all other squares are free. The starting location of the cyclist is marked by “S'' and the target is marked by “T''.
The input terminates with two zeros for M and N.
输出
For each test case first print the test case number on a separate line, as shown in the sample output. If the target location can be reached by the cyclist, print the minimum amount of time (in seconds) required to reach it in the format shown below. Otherwise print “destination not reachable".
Print a blank line between two successive test cases.
样例输入
3
S#T
10 10
#S.......#
#..#.##.##
#.##.##.##
.#....##.#
##.##..#.#
#..#.##...
#......##.
..##.##...
#.###...#.
#.....###T
0 0
样例输出
Case #1
destination not reachable
Case #2
minimum time = 49 sec
参考代码
暂无
解析
暂无
