rohacik = [ [00,10,01], [00,10,11], [10,11,01], [00,01,11] ]
stvorcek = [ [00,10,01,11] ]
hadik = [ [00,01,11,12], [01,11,10,20] ]
tecko = [ [01,11,10,12], [01,11,00,02], [10,11,00,20], [10,11,01,21] ]
krizik = [ [10,01,11,21,12] ]
ciarka = [ [00,01,02], [00,10,20] ]
elko = [ [00,01,11,21], [00,10,20,21], [00,10,01,02], [02,10,11,12] ]

$piece_shapes = [ krizik, krizik, hadik, hadik, tecko, tecko, stvorcek, stvorcek,
    elko, elko, ciarka, ciarka, rohacik, rohacik, rohacik, rohacik ]

def try_piece(field, ptype, piece)
  pdir, px, py = piece
  $piece_shapes[ptype][pdir].each do |c|
    xoff = c/10; yoff = c%10
    return false if px+xoff >= 10 or py+yoff >= 6
    return false if field[py+yoff][px+xoff]
  end
  return true
end

def render_field(pieces)
  field = Array.new(6).map{ Array.new(10) }
  pieces.each_with_index do |piece, ptype|
    pdir, px, py = piece
    $piece_shapes[ptype][pdir].each do |c|
      xoff = c/10; yoff = c%10
      field[py+yoff][px+xoff] = ptype
    end
  end
  return field
end

def found_solution(pieces)
  print `clear`
  puts "---------------"
  field = render_field(pieces)
  field.each { |row| puts row.map{ |f| f ? (65+f).chr : "." }.join }
  exit if pieces.length == $piece_shapes.length
end

def try_solution(pieces)
  return found_solution(pieces) if pieces.length == $piece_shapes.length
  field = render_field(pieces); next_ptype = pieces.length
  $timer = ($timer+1)%50; found_solution(pieces) if $timer == 0
  $piece_shapes[next_ptype].length.times do |pdir| 10.times do |px| 6.times do |py|
    $solutions_to_try << (pieces + [[pdir, px, py]]) if try_piece(field, next_ptype, [pdir, px, py])
  end end end
end

$progress = 0; $timer = 0
$solutions_to_try = [ [] ]
while $solutions_to_try.length > 0 do try_solution($solutions_to_try.pop) end