Monty Hall Problem demonstrated in Ruby

monty_hall.rb

class Game  
  attr_accessor :doors
  attr_reader :correct_door
  def initialize(door_count: )
    chosen_door = (1..door_count).to_a.sample
    @doors = door_count.times.map.with_index do |d, i| 
      Door.new(i+1 == chosen_door)
    end
    @correct_door = @doors.detect(&:correct?)
  end  
  
  def remove_one_door!(not_door: )
    removing = @doors.detect { |d| d != not_door && !d.correct? }
    @doors.delete(removing)
  end
end

class Door
  attr_reader :correct
  alias correct? correct
  def initialize(correct)
    @correct = !!correct 
  end
end

class Try
  attr_reader :player
  attr_reader :game
  attr_reader :outcome
  def initialize(player:, game:)
    @player = player
    @game   = game
    @outcome = nil
  end

  def play!
    player.make_choice!(game)
    game.remove_one_door!(not_door: player.chosen_door)
    player.make_choice!(game)
    @outcome = game.correct_door == player.chosen_door
  end
  
  def win?
    outcome == true
  end
end

class Player
  attr_accessor :strategy
  attr_accessor :chosen_door
  
  def initialize(strategy)
    @strategy = strategy
  end
  
  def make_choice!(game)
    if chosen_door && strategy == :stick
      return chosen_door
    else
      return @chosen_door = game.doors.sample
    end
  end
end

TIMES_PLAYED = 1_000_000
win_count = 0
TIMES_PLAYED.times do
  try = Try.new(player: Player.new(:stick), game: Game.new(door_count: 3))
  win_count += 1 if try.play! && try.win?
end
puts "Stick wins: #{win_count} #{Rational(win_count, TIMES_PLAYED).to_f * 100}%"

win_count = 0

TIMES_PLAYED.times do
  try = Try.new(player: Player.new(:switch), game: Game.new(door_count: 3))
  win_count += 1 if try.play! && try.win?
end
puts "Switch wins: #{win_count} #{Rational(win_count, TIMES_PLAYED).to_f * 100}%"

Stick wins: 332984 (33.2984%)
Switch wins: 499476 (49.947599999999994%)