diff options
| -rw-r--r-- | aoc2023-other/day-10/day-10.rkt | 92 | ||||
| -rw-r--r-- | aoc2023/src/day10/.gitignore | 1 | ||||
| -rw-r--r-- | aoc2023/src/day10/solve.gleam | 25 | ||||
| -rw-r--r-- | aoc2023/src/day2/solve.gleam | 2 | ||||
| -rw-r--r-- | aoc2023/test/day10/day10_test.gleam | 38 |
5 files changed, 157 insertions, 1 deletions
diff --git a/aoc2023-other/day-10/day-10.rkt b/aoc2023-other/day-10/day-10.rkt new file mode 100644 index 0000000..f9255bc --- /dev/null +++ b/aoc2023-other/day-10/day-10.rkt @@ -0,0 +1,92 @@ +#lang racket + +(require advent-of-code + threading) + +(struct posn (r c) #:transparent) + +(define/match (add-posns _p1 _p2) + [((posn x1 y1) (posn x2 y2)) (posn (+ x1 x2) (+ y1 y2))]) + +(define go-north (posn -1 0)) +(define go-south (posn 1 0)) +(define go-east (posn 0 1)) +(define go-west (posn 0 -1)) + +(define initial-directions + (list (cons go-north '(#\| #\7 #\F)) + (cons go-south '(#\| #\J #\L)) + (cons go-east '(#\- #\J #\7)) + (cons go-west '(#\- #\F #\L)))) + +(define/match (pipe-neighbors _pipe) + [(#\|) (list go-north go-south)] + [(#\-) (list go-east go-west)] + [(#\L) (list go-north go-east)] + [(#\F) (list go-south go-east)] + [(#\7) (list go-south go-west)] + [(#\J) (list go-north go-west)]) + +(define (make-pipe-grid in) + (for*/hash ([(row r) (in-indexed (string-split in "\n"))] [(ch c) (in-indexed (string->list row))]) + (values (posn (add1 r) (add1 c)) ch))) + +(define (get-valid-S-neighbors S grid) + (for/list ([dir (in-list initial-directions)] + #:do [(match-define (cons d valid) dir)] + #:do [(define neighbor (add-posns d S))] + #:when (member (hash-ref grid neighbor 'none) valid)) + neighbor)) + +(define (to-next-pipe current previous grid [acc '()]) + (cond + [(equal? (hash-ref grid current #f) #\S) acc] + [else + (define next + (for/first ([d (in-list (pipe-neighbors (hash-ref grid current)))] + #:do [(define neighbor (add-posns d current))] + #:unless (equal? neighbor previous)) + neighbor)) + (~> next (to-next-pipe _ current grid (cons current acc)))])) + +;; part 1 +(define input (fetch-aoc-input (find-session) 2023 10 #:cache #true)) + +(define pipe-grid (make-pipe-grid input)) + +(define S-posn + (for/first ([(k v) (in-hash pipe-grid)] #:when (equal? v #\S)) + k)) + +(define S-neighbors (get-valid-S-neighbors S-posn pipe-grid)) + +(define pipe-loop (to-next-pipe (first S-neighbors) S-posn pipe-grid '())) + +(/ (add1 (length pipe-loop)) 2) + +;; part 2 +(define pipe-loop-set (~> (list->set pipe-loop) (set-add S-posn))) + +(define (trace-rays pt pipes grid) + (cond + [(set-member? pipes pt) #f] + [else (odd? (trace-ray pt pipes grid))])) + +(define (trace-ray pt pipes grid) + (define row (posn-r pt)) + (for/fold ([acc 0] [corner #f] #:result acc) + ([col (in-naturals (posn-c pt))] + #:do [(define test-pt (posn row col))] + #:break (not (hash-has-key? grid test-pt)) + #:when (set-member? pipes test-pt)) + (define pipe (hash-ref grid test-pt)) + (match* (pipe corner) + [(#\| #f) (values (add1 acc) #f)] ; vertical crossing + [((or #\F #\L) #f) (values acc pipe)] + [(#\J #\F) (values (add1 acc) #f)] ; a ┏━┛ shape counts as a vertical crossing + [(#\7 #\L) (values (add1 acc) #f)] + [(#\7 #\F) (values acc #f)] ; a ┏━┓ shape doesn't count + [(#\J #\L) (values acc #f)] + [(_ _) (values acc corner)]))) + +(~> pipe-grid hash-keys (count (λ~> (trace-rays pipe-loop-set pipe-grid)) _)) diff --git a/aoc2023/src/day10/.gitignore b/aoc2023/src/day10/.gitignore new file mode 100644 index 0000000..ae40cea --- /dev/null +++ b/aoc2023/src/day10/.gitignore @@ -0,0 +1 @@ +input.txt
\ No newline at end of file diff --git a/aoc2023/src/day10/solve.gleam b/aoc2023/src/day10/solve.gleam new file mode 100644 index 0000000..43dba6d --- /dev/null +++ b/aoc2023/src/day10/solve.gleam @@ -0,0 +1,25 @@ +import adglent.{First, Second} +import gleam/io + +pub fn part1(input: String) { + todo as "Implement solution to part 1" +} + +pub fn part2(input: String) { + todo as "Implement solution to part 2" +} + +pub fn main() { + let assert Ok(part) = adglent.get_part() + let assert Ok(input) = adglent.get_input("10") + case part { + First -> + part1(input) + |> adglent.inspect + |> io.println + Second -> + part2(input) + |> adglent.inspect + |> io.println + } +} diff --git a/aoc2023/src/day2/solve.gleam b/aoc2023/src/day2/solve.gleam index 22470ab..608955f 100644 --- a/aoc2023/src/day2/solve.gleam +++ b/aoc2023/src/day2/solve.gleam @@ -22,7 +22,7 @@ fn parse(input: String) -> List(List(Game)) { "red" -> Game(..acc, red: n) "blue" -> Game(..acc, blue: n) "green" -> Game(..acc, green: n) - _ -> panic as { "unrecognized color " <> color } + _ -> panic as "unrecognized color" } } diff --git a/aoc2023/test/day10/day10_test.gleam b/aoc2023/test/day10/day10_test.gleam new file mode 100644 index 0000000..0df62a3 --- /dev/null +++ b/aoc2023/test/day10/day10_test.gleam @@ -0,0 +1,38 @@ +import gleam/list +import showtime/tests/should +import adglent.{type Example, Example} +import day10/solve + +type Problem1AnswerType = + String + +type Problem2AnswerType = + String + +/// Add examples for part 1 here: +/// ```gleam +///const part1_examples: List(Example(Problem1AnswerType)) = [Example("some input", "")] +/// ``` +const part1_examples: List(Example(Problem1AnswerType)) = [] + +/// Add examples for part 2 here: +/// ```gleam +///const part2_examples: List(Example(Problem2AnswerType)) = [Example("some input", "")] +/// ``` +const part2_examples: List(Example(Problem2AnswerType)) = [] + +pub fn part1_test() { + part1_examples + |> should.not_equal([]) + use example <- list.map(part1_examples) + solve.part1(example.input) + |> should.equal(example.answer) +} + +pub fn part2_test() { + part2_examples + |> should.not_equal([]) + use example <- list.map(part2_examples) + solve.part2(example.input) + |> should.equal(example.answer) +} |