# coding=utf-8

id = 172
group = 'denotational_semantics'
number = 81
visible = True
facts = None

solution = '''\
prog_8puzzle --> [begin], instructs172, [end].

instructs172 --> instr172.
instructs172 --> instr172, instructs172.

instr172 --> [left].
instr172 --> [right].
instr172 --> [up].
instr172 --> [down].
'''