第29回オフラインリアルタイムどう書く「サイコロの展開図」の ruby による実装

PATTERNS = %w(
  12S/453 1T6/D45 146/53D 15S/3D4
  215/T64 6T1/54D 2S5/41T 3D4/15S
  512/46T 41T/2S5 453/12S 53D/146
).flat_map{ |x| [x,x.reverse] }

def solve( src )
  re=/#{src.tr("xyzw", "....")}/
  m=PATTERNS.select{ |x| re===x }
  case m.size
  when 0; 
    "none"
  when 1
    src.chars.zip( m[0].chars )
      .select{ |a,b| a!=b }
      .map{ |c| c.join("=") }
      .join(",")
  else
    "many"
  end
end

DATA.map{ |line|
  id, src, expected = line.split(/\s+/)
  actual = solve(src)
  (actual == expected).tap do |ok|
    puts '***NG*** : %s %s->%s ( %s )' % [id, src, actual, expected] unless ok
  end
}.tap{ |x| puts( "ok:%d / NG:%d" % [ x.count(true), x.count(false) ] ) }

__END__
0 Tx4/5yz x=1,y=S,z=2
1 14S/xyz none
2 1w6/xyz many

# 目の図形を90度回す
def rot_face(f)
  key="D2T3S6114455"
  key[ key.index(f)^1 ]
end

# サイコロを90度回す
def rot_dice(s)
  [rot_face(s[5]), s[0], (s[1]), 
   "/", 
   rot_face(s[4]), rot_face(s[2]), rot_face(s[6])
  ].join
end

# 展開図の可能なパターンをすべて列挙する
def enum_patterns( pats={}, c="146/53D", &block)
  return if pats[c]
  pats[c]=true
  block.(c)
  enum_patterns(pats, c.reverse, &block)
  enum_patterns(pats, rot_dice(c), &block)
end

#解く
def solve( src )
  re=/#{src.tr("xyzw", "....")}/
  m = enum_for(:enum_patterns).select{ |x| re===x }
  case m.size
  when 0
    "none"
  when 1
    src.chars.zip( m[0].chars )
      .select{ |a,b| a!=b }
      .map{ |c| c.join("=") }
      .join(",")
  else
    "many"
  end
end