aboutsummaryrefslogtreecommitdiff
path: root/aoc2023/src/day4/solve.gleam
diff options
context:
space:
mode:
Diffstat (limited to 'aoc2023/src/day4/solve.gleam')
-rw-r--r--aoc2023/src/day4/solve.gleam98
1 files changed, 0 insertions, 98 deletions
diff --git a/aoc2023/src/day4/solve.gleam b/aoc2023/src/day4/solve.gleam
deleted file mode 100644
index 34d6098..0000000
--- a/aoc2023/src/day4/solve.gleam
+++ /dev/null
@@ -1,98 +0,0 @@
-import adglent.{First, Second}
-import gleam/bool
-import gleam/dict.{type Dict}
-import gleam/int
-import gleam/io
-import gleam/list
-import gleam/option.{None, Some}
-import gleam/result
-import gleam/set.{type Set}
-import gleam/string
-
-type Card {
- Card(number: Int, winners: Int)
-}
-
-fn numbers_to_set(str: String) -> Set(Int) {
- str
- |> string.split(" ")
- |> list.map(int.parse)
- |> result.values()
- |> set.from_list()
-}
-
-fn parse_card(card: String) -> Card {
- let assert Ok(#("Card" <> n_str, rest)) = string.split_once(card, ": ")
- let assert Ok(#(winning_str, has_str)) = string.split_once(rest, " | ")
- let assert Ok(n) = int.parse(string.trim(n_str))
-
- let winning = numbers_to_set(winning_str)
- let has = numbers_to_set(has_str)
- let winners = set.size(set.intersection(winning, has))
-
- Card(number: n, winners: winners)
-}
-
-fn win_points(n: Int) {
- bool.guard(n < 2, n, fn() { 2 * win_points(n - 1) })
-}
-
-pub fn part1(input: String) {
- use acc, c <- list.fold(string.split(input, "\n"), 0)
- c
- |> parse_card
- |> fn(c: Card) { win_points(c.winners) }
- |> int.add(acc)
-}
-
-fn win_more_cards(cards: List(String), count: Dict(Int, Int)) {
- case cards {
- [] ->
- count
- |> dict.values
- |> int.sum
- [raw_card, ..rest] -> {
- let card = parse_card(raw_card)
- case card.winners {
- 0 -> win_more_cards(rest, count)
- n -> win_more_cards(rest, update_counts(n, card, count))
- }
- }
- }
-}
-
-fn update_counts(n: Int, card: Card, count: Dict(Int, Int)) -> Dict(Int, Int) {
- let assert Ok(bonus) = dict.get(count, card.number)
- use acc, n <- list.fold(list.range(card.number + 1, card.number + n), count)
- use c <- dict.update(acc, n)
- case c {
- Some(i) -> i + bonus
- None -> panic as "won a card that doesn't exist in the card pile"
- }
-}
-
-pub fn part2(input: String) {
- let cards = string.split(input, "\n")
-
- let count =
- list.range(1, list.length(cards))
- |> list.map(fn(n) { #(n, 1) })
- |> dict.from_list()
-
- win_more_cards(cards, count)
-}
-
-pub fn main() {
- let assert Ok(part) = adglent.get_part()
- let assert Ok(input) = adglent.get_input("4")
- case part {
- First ->
- part1(input)
- |> adglent.inspect
- |> io.println
- Second ->
- part2(input)
- |> adglent.inspect
- |> io.println
- }
-}