Sophie DeBenedetto SophieDeBenedetto

## accountant_22.ex
def product_of_equals_twenty_twenty(_list, product) when product != nil, do: product

## accountant_21.ex
defp get_two([first | [second | _rest]])
    when equals_twenty_twenty(first, second) do
  first * second
end

## accountant_20.ex
defmodule Accountant do
  @sum 2020
  defguard equals_twenty_twenty(first, second) when first + second == @sum
  # ...

## accountant_19.ex
defp get_two(list) when length(list) == 1, do: nil

## accountant_18.ex
def product_of_equals_twenty_twenty([_head | tail] = list, _product) do
  product_of_equals_twenty_twenty(tail, get_two(list))
end

## accountant_17.ex
def product_of_equals_twenty_twenty([_head | tail] = list, _product) do
  product_of_equals_twenty_twenty(tail, get_two(list))
end

## accountant_16.ex
def product_of_equals_twenty_twenty(_list, product) when product != nil, do: product

## accountant_15.ex
def product_of_equals_twenty_twenty([_head | tail] = list, _product) do
  product_of_equals_twenty_twenty(tail, get_two(list))
end

## accountant_14.ex
Accountant.product_of_equals_twenty_twenty([979, 1721, 366, 299, 675, 1456])

## accountant_13.ex
defp get_two(list) when length(list) == 1, do: nil
	defp get_two([first \| [second \| _rest]])
	when equals_twenty_twenty(first, second) do
	first * second
	end
	defmodule Accountant do
	@sum 2020
	defguard equals_twenty_twenty(first, second) when first + second == @sum
	# ...
	def product_of_equals_twenty_twenty([_head \| tail] = list, _product) do
	product_of_equals_twenty_twenty(tail, get_two(list))
	end