# File lib/quiz1/t/solutions/Dennis Ranke/solitaire.rb, line 16
  def next_letter
    ##
    # move the jokers
    ##

    2.times do |j|
      # find the joker
      index = @deck.index(52 + j)

      # remove it from the deck
      @deck.delete_at(index)

      # calculate new index
      index = ((index + j) % 53) + 1

      # insert the joker at that index
      @deck[index, 0] = 52 + j
    end

    ##
    # do the tripple cut
    ##

    # first find both jokers
    a = @deck.index(52)
    b = @deck.index(53)

    # sort the two indeces
    low, hi = [a, b].sort

    # get the lower and upper parts of the deck
    upper = @deck.slice!((hi + 1)..-1)
    lower = @deck.slice!(0, low)

    # swap them
    @deck = upper + @deck + lower

    ##
    # do the count cut
    ##

    # find out the number of cards to cut
    count = value_at(53)

    # remove them from the top of the deck
    cards = @deck.slice!(0, count)

    # reinsert them just above the lowest card
    @deck[-1, 0] = cards

    return letter_at(value_at(0))
  end