Alpha test

guessing_game.rb

class GuessingGame

  attr_reader :total_tricks, :trick_config, :results

  def initialize(trick_config)
    @total_tricks = trick_config.slice!(0).to_i 
    @trick_config = trick_config
    @results = []
  end

  def perform
    @trick_config.each_slice(10).each_with_index { |line, idx| build(line, idx) }
  end

  private

    def build(l, idx)
      tricks = get_card_grid(l)
      @results << "Case #%s: %s" % [idx+1, validate(tricks)]
    end

    def validate(trick)
      return 'Volunteer cheated!' if trick[0] === trick[1]
      intersection = trick[0] & trick[1]
      return intersection[0] if intersection.any?
      'Bad magician!'
    end  

    def get_card_grid(line)
      2.times.map do |index|
        start = index*5
        range = (start+1..start+14)
        line[range][(line[start].to_i)-1].split
      end
    end

end

magic_trick.rb

class MagicTrick

  attr_reader :tricks

  def initialize(tricks, file_input = './magic_trick_input.txt')
    @tricks = tricks
    parse File.read(file_input)
  end

  def parse(contents)
    tricks = @tricks.new contents.split("\n")
    tricks.perform
    puts tricks.results
  end

end

magic_trick = MagicTrick.new(GuessingGame)

magic_trick_input.txt

3
2
1 2 3 4
5 6 7 8
9 10 11 12
13 14 15 16
3
1 2 5 4
3 11 6 15
9 10 7 12
13 14 8 16
2
1 2 3 4
5 6 7 8
9 10 11 12
13 14 15 16
2
1 2 3 4
5 6 7 8
9 10 11 12
13 14 15 16
2
1 2 3 4
5 6 7 8
9 10 11 12
13 14 15 16
3
1 2 3 4
5 6 7 8
9 10 11 12
13 14 15 16