Merge branch 'main' of https://github.com/hunkyjimpjorps/AdventOfCode

2 files changed, 94 insertions, 0 deletions

diff --git a/aoc2018/day-03/day-03.rkt b/aoc2018/day-03/day-03.rkt
new file mode 100644
index 0000000..b486361
--- /dev/null
+++ b/aoc2018/day-03/day-03.rkt
@@ -0,0 +1,51 @@
+#lang racket
+
+(require advent-of-code
+         threading
+         data/applicative
+         data/monad
+         megaparsack
+         megaparsack/text)
+
+(struct claim (number start-x start-y size-x size-y) #:transparent)
+
+(define claim/p
+  (do (char/p #\#)
+      [number <- integer/p]
+      (string/p " @ ")
+      [start-x <- integer/p]
+      (char/p #\,)
+      [start-y <- integer/p]
+      (string/p ": ")
+      [size-x <- integer/p]
+      (char/p #\x)
+      [size-y <- integer/p]
+      (pure (claim number start-x start-y size-x size-y))))
+
+(define (parse-claim str)
+  (parse-result! (parse-string claim/p str)))
+
+(define (make-claim ht cl)
+  (for*/fold ([fabric ht])
+             ([x (in-range (claim-start-x cl) (+ (claim-start-x cl) (claim-size-x cl)))]
+              [y (in-range (claim-start-y cl) (+ (claim-start-y cl) (claim-size-y cl)))])
+    (hash-update fabric (cons x y) add1 0)))
+
+(define claims
+  (~> (port->lines (open-aoc-input (find-session) 2018 3 #:cache #true)) (map parse-claim _)))
+
+(define claimed-fabric
+  (for/fold ([fabric (hash)]) ([cl (in-list claims)])
+    (make-claim fabric cl)))
+
+;; part 1
+(for/sum ([claim-count (in-list (hash-values claimed-fabric))] #:when (< 1 claim-count)) 1)
+
+;; part 2
+(define (uncontested-claim? fabric cl)
+  (for*/and ([x (in-range (claim-start-x cl) (+ (claim-start-x cl) (claim-size-x cl)))]
+             [y (in-range (claim-start-y cl) (+ (claim-start-y cl) (claim-size-y cl)))])
+    (= 1 (hash-ref fabric (cons x y)))))
+
+(for/first ([cl (in-list claims)] #:when (uncontested-claim? claimed-fabric cl))
+  (claim-number cl))
diff --git a/aoc2018/day-04/day-04.rkt b/aoc2018/day-04/day-04.rkt
new file mode 100644
index 0000000..3660099
--- /dev/null
+++ b/aoc2018/day-04/day-04.rkt
@@ -0,0 +1,43 @@
+#lang racket
+
+(require advent-of-code
+         data/applicative
+         data/monad
+         megaparsack
+         megaparsack/text
+         threading)
+
+(struct entry (month day hour minute message) #:transparent)
+
+(define (parse-message chrs)
+  (define str (apply string chrs))
+  (match str
+    ["wakes up" 'awake]
+    ["falls asleep" 'asleep]
+    [shift (~> shift (string-trim "Guard #") (string-trim " begins shift") string->number)]))
+
+(define entry/p
+  (do (string/p "[1518-")
+      [month <- integer/p]
+      (char/p #\-)
+      [day <- integer/p]
+      space/p
+      [hour <- integer/p]
+      (char/p #\:)
+      [minute <- integer/p]
+      (string/p "] ")
+      [message <- (many/p any-char/p)]
+      (pure (entry month day hour minute (parse-message message)))))
+
+(define (parse-entry str)
+  (parse-result! (parse-string entry/p str)))
+
+(define entries
+  (~> (port->lines (open-aoc-input (find-session) 2018 4 #:cache #true)) (map parse-entry _)))
+
+(define sorted-entries
+  (~> entries
+      (sort < #:key entry-minute)
+      (sort < #:key entry-hour)
+      (sort < #:key entry-day)
+      (sort < #:key entry-month)))