Sokoban: Difference between revisions

=={{header|Julia}}==

{{trans|Go}}

<lang julia>struct BoardState

board::String

csol::String

position::Int

end

function move(s::BoardState, dpos)

buffer = Vector{UInt8}(deepcopy(s.board))

if s.board[s.position] == '@'

buffer[s.position] = ' '

else

buffer[s.position] = '.'

end

newpos = s.position + dpos

if s.board[newpos] == ' '

buffer[newpos] = '@'

else

buffer[newpos] = '+'

end

String(buffer)

end

function push(s::BoardState, dpos)

newpos = s.position + dpos

boxpos = newpos + dpos

if s.board[boxpos] != ' ' && s.board[boxpos] != '.'

return ""

end

buffer = Vector{UInt8}(deepcopy(s.board))

if s.board[s.position] == '@'

buffer[s.position] = ' '

else

buffer[s.position] = '.'

end

if s.board[newpos] == '$'

buffer[newpos] = '@'

else

buffer[newpos] = '+'

end

if s.board[boxpos] == ' '

buffer[boxpos] = '$'

else

buffer[boxpos] = '*'

end

String(buffer)

end

function solve(board)

width = findfirst("\n", board[2:end])[1] + 1

dopt = (u = -width, l = -1, d = width, r = 1)

visited = Dict(board => true)

open::Vector{BoardState} = [BoardState(board, "", findfirst("@", board)[1])]

while length(open) > 0

s1 = open[1]

open = open[2:end]

for dir in keys(dopt)

newpos = s1.position + dopt[dir]

x = s1.board[newpos]

if x == '$' || x == '*'

newboard = push(s1, dopt[dir])

if newboard == "" || haskey(visited, newboard)

continue

end

newsol = s1.csol * uppercase(string(dir))

if findfirst(".", newboard) == nothing

return newsol

end

elseif x == ' ' || x == '.'

newboard = move(s1, dopt[dir])

if haskey(visited, newboard)

continue

end

newsol = s1.csol * string(dir)

else

continue

end

open = push!(open, BoardState(newboard, newsol, newpos))

visited[newboard] = true

end

end

"No solution" # we should only get here if no solution to the sokoban

end

const testlevel = strip(raw"""

#######

# #

# #

#. # #

#. $$ #

#.$$ #

#.# @#

#######""")

println("For sokoban level:\n$testlevel\n...solution is :\n$(solve(testlevel))")

</lang>{{output}}<pre>

For sokoban level:

#######

# #

# #

#. # #

#. $$ #

#.$$ #

#.# @#

#######

...solution is :

ulULLulDDurrrddlULrruLrUruLLLulDD

</pre>