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Diffstat (limited to 'aoc2023-gleam/src/day19/solve.gleam')
| -rw-r--r-- | aoc2023-gleam/src/day19/solve.gleam | 255 |
1 files changed, 0 insertions, 255 deletions
diff --git a/aoc2023-gleam/src/day19/solve.gleam b/aoc2023-gleam/src/day19/solve.gleam deleted file mode 100644 index 186e783..0000000 --- a/aoc2023-gleam/src/day19/solve.gleam +++ /dev/null @@ -1,255 +0,0 @@ -import adglent.{First, Second} -import gleam/io -import gleam/string -import gleam/dict.{type Dict} -import gleam/order.{type Order, Gt, Lt} -import gleam/regex.{type Match, Match} -import gleam/list -import gleam/option.{Some} -import gleam/int - -type Rating { - XtremelyCool - Musical - Aerodynamic - Shiny -} - -type Part { - Part(x: Int, m: Int, a: Int, s: Int) -} - -type Action { - Accept - Reject - SendTo(String) -} - -type Rule { - If(rating: Rating, comparison: Order, threshold: Int, do: Action) - Just(do: Action) -} - -type Workflow = - Dict(String, List(Rule)) - -type Interval { - Interval(min: Int, max: Int) -} - -type PartRange { - PartRange(x: Interval, m: Interval, a: Interval, s: Interval) -} - -fn parse_workflow(input: String) -> Workflow { - let assert Ok(re) = regex.from_string("(.*){(.*)}") - - use acc, line <- list.fold(string.split(input, "\n"), dict.new()) - let assert [Match(submatches: [Some(name), Some(all_rules)], ..)] = - regex.scan(re, line) - let rules = - string.split(all_rules, ",") - |> parse_rules - dict.insert(acc, name, rules) -} - -fn parse_rules(rules: List(String)) -> List(Rule) { - let assert Ok(re_rule) = regex.from_string("(.*)(>|<)(.*):(.*)") - use rule <- list.map(rules) - case regex.scan(re_rule, rule) { - [Match(submatches: [Some(r), Some(c), Some(t), Some(i)], ..)] -> - If(to_rating(r), to_comp(c), to_val(t), to_instruction(i)) - _nomatch -> Just(to_instruction(rule)) - } -} - -fn to_instruction(rule: String) { - case rule { - "A" -> Accept - "R" -> Reject - name -> SendTo(name) - } -} - -fn to_rating(rating: String) { - case rating { - "x" -> XtremelyCool - "m" -> Musical - "a" -> Aerodynamic - _s -> Shiny - } -} - -fn get_rating(part: Part, rating: Rating) -> Int { - case rating { - XtremelyCool -> part.x - Musical -> part.m - Aerodynamic -> part.a - Shiny -> part.s - } -} - -fn to_comp(comp: String) { - case comp { - "<" -> Lt - _gt -> Gt - } -} - -fn to_val(val: String) { - let assert Ok(n) = int.parse(val) - n -} - -fn parse_parts(input: String) -> List(Part) { - let assert Ok(re) = regex.from_string("{x=(.*),m=(.*),a=(.*),s=(.*)}") - - use part <- list.map(string.split(input, "\n")) - let assert [Match(submatches: [Some(x), Some(m), Some(a), Some(s)], ..)] = - regex.scan(re, part) - Part(to_val(x), to_val(m), to_val(a), to_val(s)) -} - -fn start_evaluating_workflow(part: Part, workflow: Workflow) -> Int { - evaluate_workflow(part, "in", workflow) -} - -fn evaluate_workflow(part: Part, name: String, workflow: Workflow) -> Int { - let assert Ok(rules) = dict.get(workflow, name) - case evaluate_rules(part, rules) { - Accept -> part.x + part.m + part.a + part.s - Reject -> 0 - SendTo(name) -> evaluate_workflow(part, name, workflow) - } -} - -fn evaluate_rules(part: Part, rules: List(Rule)) -> Action { - case rules { - [] -> panic - [Just(do), ..] -> do - [If(rating, comparison, threshold, do), ..rest] -> - case int.compare(get_rating(part, rating), threshold) == comparison { - True -> do - False -> evaluate_rules(part, rest) - } - } -} - -pub fn part1(input: String) { - let assert Ok(#(workflows_str, parts_str)) = string.split_once(input, "\n\n") - - let workflows = parse_workflow(workflows_str) - let parts = parse_parts(parts_str) - - list.map(parts, start_evaluating_workflow(_, workflows)) - |> int.sum - |> string.inspect -} - -fn size(interval: Interval) { - interval.max - interval.min + 1 -} - -fn all_in_range(pr: PartRange) { - size(pr.x) * size(pr.m) * size(pr.a) * size(pr.s) -} - -fn get_partrange(pr: PartRange, rating: Rating) -> Interval { - case rating { - XtremelyCool -> pr.x - Musical -> pr.m - Aerodynamic -> pr.a - Shiny -> pr.s - } -} - -fn update_partrange(pr: PartRange, rating: Rating, i: Interval) -> PartRange { - case rating { - XtremelyCool -> PartRange(..pr, x: i) - Musical -> PartRange(..pr, m: i) - Aerodynamic -> PartRange(..pr, a: i) - Shiny -> PartRange(..pr, s: i) - } -} - -pub fn part2(input: String) { - let assert Ok(#(workflows_str, _)) = string.split_once(input, "\n\n") - - let workflow = parse_workflow(workflows_str) - let start = Interval(1, 4000) - - PartRange(start, start, start, start) - |> evaluate_workflow_on_range("in", workflow) - |> string.inspect -} - -fn evaluate_workflow_on_range( - pr: PartRange, - name: String, - workflow: Workflow, -) -> Int { - let assert Ok(rules) = dict.get(workflow, name) - evaluate_rules_on_range(pr, rules, workflow) -} - -fn evaluate_rules_on_range( - pr: PartRange, - rules: List(Rule), - workflow: Workflow, -) -> Int { - case rules { - [Just(Accept), ..] -> all_in_range(pr) - [Just(Reject), ..] -> 0 - [Just(SendTo(name)), ..] -> evaluate_workflow_on_range(pr, name, workflow) - [If(rating, comparison, t, action), ..rest] -> { - let mod_i = get_partrange(pr, rating) - case comparison { - Lt -> - split_range( - keep: update_partrange(pr, rating, Interval(mod_i.min, t - 1)), - and_do: action, - pass: update_partrange(pr, rating, Interval(t, mod_i.max)), - and_eval: rest, - with: workflow, - ) - _gt -> - split_range( - keep: update_partrange(pr, rating, Interval(t + 1, mod_i.max)), - and_do: action, - pass: update_partrange(pr, rating, Interval(mod_i.min, t)), - and_eval: rest, - with: workflow, - ) - } - } - [] -> panic - } -} - -fn split_range( - keep keep: PartRange, - and_do action: Action, - pass pass: PartRange, - and_eval rest: List(Rule), - with workflow: Workflow, -) -> Int { - int.add( - evaluate_rules_on_range(keep, [Just(action)], workflow), - evaluate_rules_on_range(pass, rest, workflow), - ) -} - -pub fn main() { - let assert Ok(part) = adglent.get_part() - let assert Ok(input) = adglent.get_input("19") - case part { - First -> - part1(input) - |> adglent.inspect - |> io.println - Second -> - part2(input) - |> adglent.inspect - |> io.println - } -} |