class Delta

# File lib/deltacoding.rb, line 25
def asci_decode(array_of_digits)
  decode(array_of_digits).map { |e| e.chr(Encoding::UTF_8) }.join
end

# File lib/deltacoding.rb, line 21
def asci_encode(string)
  encode(string.split('').map(&:ord))
end

# File lib/deltacoding.rb, line 13
def decode(array_of_digits)
  array_of_digits.each.with_index.each_with_object([]) do |(elem, index), arr|
    next arr << elem if index.zero?

    arr << elem + arr[index - 1]
  end
end

# File lib/deltacoding.rb, line 5
def encode(array_of_digits)
  array_of_digits.map.with_index do |elem, index|
    next elem if index.zero?

    elem - array_of_digits[index - 1]
  end
end