snowman.rb

class WordMachine

  def initialize(string)
    @letters = string.split('')
  end

  def words
    @letters.permutation.to_a.map(&:join).uniq.sort
  end

  def find(string)
    words.find_index(string) + 1
  end

end

position = WordMachine.new('snowman').find('snowman')

puts sum_of_digits = position.to_s.split('').map(&:to_i).reduce(&:+)