テトロミノビンゴをRubyで解く

問題はこちら
http://nabetani.sakura.ne.jp/codeiq/tetromino_bingo/

require 'open-uri'
DATA_URI = 'http://nabetani.sakura.ne.jp/codeiq/tetromino_bingo/data.txt'

def find_num_pos(num, board)
  board.each_with_index{|row, y|
    row.each_with_index{|cell, x|
      return [y, x] if cell == num
    }
  }
  nil
end

def check_tetro(board, holes)
  holes_cur = holes
  holes_new = nil
  holes_next = holes 
  begin
    holes_new = holes_next
    holes_next = []
    holes_new.each {|y, x|
      [[1,0],[0,1],[-1,0],[0,-1]].each {|dy, dx|
        ny, nx = y + dy, x + dx
        next unless board[ny][nx].nil?
        nyx = [ny, nx]
        next if holes_cur.include?(nyx)
        next if holes_next.include?(nyx)
        holes_next << nyx
      }
    }
    holes_cur += holes_next
  end while(!holes_next.empty?)
  holes_cur.size == 4 ? holes_cur : nil
end

def adjust_pos(holes)
  y_min = holes.map(&:first).min
  x_min = holes.map(&:last).min
  holes.map{|y, x| [y - y_min, x - x_min]}.sort
end

def rotate(holes)
  adjust_pos(holes.map{|y, x| [-x, y]})
end

def judge_tetro_char(holes)
  tetros = {
    [[0,0],[1,0],[2,0],[3,0]] => 'I',
    [[0,0],[1,0],[2,0],[2,1]] => 'L',
    [[0,0],[0,1],[1,0],[1,1]] => 'O',
    [[0,0],[1,0],[1,1],[2,1]] => 'S',
    [[0,0],[1,0],[1,1],[2,0]] => 'T',
  }
  mirror_holes = holes.map{|y, x| [-y, x]}
  4.times{
    holes = rotate(holes)
    return tetros[holes] if tetros[holes]
    mirror_holes = rotate(mirror_holes)
    return tetros[mirror_holes] if tetros[mirror_holes]
  }
  "-"
end

def solve(nums, q)
  board = [[0]*7] + q.split('/').map{|e| [0] + e.split(',').map(&:to_i) + [0]} + [[0]*7]

  nums.each{|num|
    y, x = find_num_pos(num, board)
    if x
      board[y][x] = nil
      holes = check_tetro(board, [[y, x]])
      return judge_tetro_char(holes) if holes
    end
  }
  "-"
end

#header, *data = DATA.readlines
header, *data = open(DATA_URI).readlines

nums = header.chop.split(',').map(&:to_i)
sums = Hash.new(0)
data.each_with_index do |line, i|
  q,a = line.chop.split(/\s+/)
  ans = solve(nums, q)
  if a
    print i.to_s + "\t" + ans
    puts ans == a ? ' o' : ' x'
  end
  sums[ans] += 1 unless ans == '-'
end
p sums
__END__
74,72,90,23,68,36,35,41,67,18,1,89,39,80,47,10,45,40,26,91,6,98,73,53,44,24,52,63,46,59,28,92,13,94,66,49,3,87,64,4,88,76,96,9,29,85,42,82,25,51,86,19,83,14,77,78,58,62,81,22,93,15,2,20,33,57,37,48,38,34,79,17,65,60,11,31,27,5,69,32,95,99,50,16,70,75,12,7,56,21,97,30,8,61,55,84,54,71,43
93,84,33,81,79/18,36,13,89,92/46,34,55,78,63/32,59,49,88,11/3,45,60,56,20   S
74,72,90,23,68/36,35,41,67,18/1,89,39,80,47/10,45,40,26,91/6,98,73,53,44    I
11,31,69,27,5/32,95,99,50,43/16,70,75,84,30/12,7,56,54,8/21,97,71,61,55 L