Monty Hall problem experiment https://en.wikipedia.org/wiki/Monty_Hall_problem

monty_hall.rb

N = 10_000
matched1 = 0
matched2 = 0

N.times do
  seq = [1, 0, 0].shuffle
  guess = rand(3)

  matched1 += 1 if seq[guess].eql?(1)

  index_zero = seq.each_with_index do |item, index|
    break index if (index != guess && item == 0)
  end

  seq.delete_at(index_zero)

  guess = guess - 1 if guess > index_zero

  matched2 += 1 if seq[guess].eql?(0)
end

puts matched1 / N.to_f
puts matched2 / N.to_f