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test_sample.doctest - simple test for rush hour solution finder
Copyright (C) 2016 Arthur de Jong
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
>>> from rush_hour import find_solutions
>>> def get_moves(board):
... """Return a list or printable solutions (steps)."""
... return [
... ','.join(move for move, board in solution)
... for solution in find_solutions(board)]
>>> board = '''
... ....AA
... ..BBCC
... rr..EF
... GGHHEF
... ...IEF
... ...IJJ
... '''.strip().split()
>>> solutions = get_moves(board)
>>> len(solutions[0].split(','))
13
>>> 'AL4,BL2,CL2,EU2,FU2,HR2,IU1,JL4,ID1,HL2,ED3,FD3,rR4' in solutions
True
With the current algorithm it is very hard to determine whether a (manually)
precomputed solution will be found because there are a lot of orders in which
steps can be taken and since we try to avoid finding moves that result in the
exact same board configuration we are bound to miss some.
>>> board = '''
... ..OOOP
... .....P
... rrAB.P
... Q.ABCC
... Q.....
... QRRR..
... '''.strip().split()
>>> solutions = get_moves(board)
>>> len(solutions[0].split(','))
6
For example, the first one is not found with the current implementation but
the second (which is basically the exact same solution) is:
>>> 'OL2,BU2,CL1,PD3,AD1,rR4' in solutions
False
>>> 'OL2,AD1,BU2,CL1,PD3,rR4' in solutions
True
Another simple example.
>>> board = '''
... ..OABB
... ..OA.C
... ..OrrC
... ..PPPD
... .....D
... ......
... '''.strip().split()
>>> solutions = get_moves(board)
>>> len(solutions[0].split(','))
9
>>> 'DD1,PR1,OD3,rL2,AD1,BL3,CU1,AU1,rR3' in solutions
False
>>> 'DD1,PR1,OD3,rL2,AD1,BL3,AU1,CU1,rR3' in solutions
True
This is the hardest example from the Rush Hour game.
>>> board = '''
... OOO..P
... .....P
... ..ArrP
... ..ABCC
... D.EBFF
... D.EQQQ
... '''.strip().split()
>>> solutions = get_moves(board)
>>> len(solutions[0].split(','))
29
The algorithm should also deal fine with larger or smaller boards, non-square
boards and longer cars.
>>> board = '''
... ....DAAAAA
... ..rrD..B..
... .......B..
... ....CCCCC.
... '''.strip().split()
>>> solutions = get_moves(board)
>>> len(solutions[0].split(','))
7
The algorithm will return nothing (empty iterator) for impossible boards.
>>> board = '''
... ....B.
... ..AAB.
... rr..B.
... ..ECCC
... ..E.D.
... FFF.D.
... '''.strip().split()
>>> len(get_moves(board))
0
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