diff --git a/2023/README.md b/2023/README.md index c988051..f919199 100644 --- a/2023/README.md +++ b/2023/README.md @@ -3,7 +3,7 @@ | S | M | T | W | T | F | S | | :-: | :-: | :-: | :-: | :-: | :-: | :-: | | | | | | | [1] | [2] | -| [3] | [4] | [5] | 6 | 7 | 8 | 9 | +| [3] | [4] | [5] | 6 | [7] | 8 | 9 | | 10 | 11 | 12 | 13 | 14 | 15 | 16 | | 17 | 18 | 19 | 20 | 21 | 22 | 23 | | 24 | 25 | | | | | | @@ -14,3 +14,5 @@ [3]: ./lib/2023/3.ex [4]: ./lib/2023/4.ex [5]: ./lib/2023/5.ex + +[7]: ./lib/2023/7.ex diff --git a/2023/lib/2023/7.ex b/2023/lib/2023/7.ex new file mode 100644 index 0000000..d87ef7d --- /dev/null +++ b/2023/lib/2023/7.ex @@ -0,0 +1,52 @@ +import AOC +import AOCHelpers + +aoc 2023, 7 do + def p1(input) do + input + |> read_input() + |> Enum.map(fn [hand, bet] -> + counts = + hand + |> Enum.frequencies() + |> Map.values() + |> Enum.sort(:desc) + + [counts, hand, bet] + end) + |> Enum.sort(&compare_hands_1/2) + |> Enum.map(&Enum.at(&1, 2)) + |> Enum.with_index(1) + |> Enum.map(fn {bet, rank} -> bet * rank end) + |> Enum.sum() + end + + def p2(_input) do + end + + def read_input(input) do + input + |> lines() + |> Enum.map(fn line -> + line + |> words() + |> map_list([&to_numeric_hand/1, &String.to_integer/1]) + end) + end + + def to_numeric_hand(str) do + str + |> letters() + |> Enum.map(fn + "A" -> 14 + "K" -> 13 + "Q" -> 12 + "J" -> 11 + "T" -> 10 + n -> String.to_integer(n) + end) + end + + def compare_hands_1([counts, hand_a, _], [counts, hand_b, _]), do: hand_a <= hand_b + def compare_hands_1([counts_a, _, _], [counts_b, _, _]), do: counts_a <= counts_b +end diff --git a/2023/lib/AOCHelpers.ex b/2023/lib/AOCHelpers.ex new file mode 100644 index 0000000..b96f17e --- /dev/null +++ b/2023/lib/AOCHelpers.ex @@ -0,0 +1,30 @@ +defmodule AOCHelpers do + def lines(string) when is_binary(string) do + String.split(string, "\n") + end + + def words(str) when is_binary(str) do + String.split(str) + end + + def letters(str) when is_binary(str) do + String.split(str, "", trim: true) + end + + @doc """ + Take a list of terms and a list of 1-arity functions and apply each function + to the coresponding term in the list of terms. + + ## Example + + iex> map_list([1, 2, 3], [&(&1 + 1), &(&1 * 100), &to_string/1]) + [2, 200, "3"] + + """ + def map_list(args, funs) do + Enum.zip_with(args, funs, fn arg, fun -> fun.(arg) end) + end + + def id(x), do: x + def always(x), do: fn -> x end +end diff --git a/README.md b/README.md index e770f5f..21d004d 100644 --- a/README.md +++ b/README.md @@ -14,7 +14,7 @@ 1. [2020] **17/50** 🌟 1. [2021] **43/50** 🌟 1. [2022] **14/50** 🌟 -1. [2023] **9/50** 🌟 +1. [2023] **10/50** 🌟 [2015]: ./2015 [2017]: ./2017