adventofcode-5.2.iex

defmodule Arvuti do
	def hashit(str, ind, result) do
		hash = :crypto.hash(:md5 , str <> to_string(ind)) |> Base.encode16()
		{pos, _} = :string.to_integer(to_char_list(String.slice(hash,5..5)))
		letter = String.slice(hash, 6..6)
		cond do
			isdone(result) ->
				result
			String.slice(hash, 0..4) == "00000" && 0 <= pos && pos < 8 && String.slice(result, pos..pos) == "_" ->
				result = String.slice(result, 0..pos-1) <> letter <> String.slice(result, pos+1..10)
				IO.puts result
				hashit(str, ind+1, result)
			true ->
				hashit(str, ind+1, result)
		end
	end
	def isdone(code) do
		String.slice(code, 0..0) != "_" && isdone(String.slice(code, 1..10))
	end
end


# IO.puts Arvuti.hashit("abc", 3231928, "________")
IO.puts Arvuti.hashit("wtnhxymk", 0, "________")