Turn Camelcase into Snakecase

snakecase.rb

output = this_is_camel_case

SPLIT words at upcase ignoring first upcase
at split add _
Join them
downcase entire string



input = 'ThisIsCamelCass'






def upcase?(letter)
  if letter.upcase == letter
    true 
  else
    false
  end
end


def snakecase(word)
  split_array = word.split('')
  snakecase_array = []


  split_array.each do |letter|
    if letter == split_array[0]
      snakecase_array << letter
    elsif upcase?(letter)
      snakecase_array << "_#{letter}"
    else
      snakecase_array << letter
    end
  end
  snakecase_array.join.downcase
end

puts snakecase(input)