day10

1 files changed, 31 insertions, 0 deletions

diff --git a/day10.clj b/day10.clj
new file mode 100644
index 0000000..b838b0d
--- /dev/null
+++ b/day10.clj
@@ -0,0 +1,31 @@
+(ns org.vuxu.aoc2021.day10
+  (:require [clojure.string :as str]))
+
+(defn fix [f x]
+  (loop [x x]
+    (let [fx (f x)]
+      (if (= x fx) x (recur fx)))))
+
+(let [[incomplete corrupted]
+      (->> (slurp "day10")
+           (str/split-lines)
+           (map (partial fix #(str/replace % #"\(\)|\[\]|\{\}|<>" "")))
+           ((juxt filter remove) (partial re-find #"[)}>\]]")))]
+  (def incomplete incomplete)
+  (def corrupted corrupted))
+
+(def part1
+  (->> incomplete
+       (map (partial some #{\) \] \} \>}))
+       (map {\) 3 \] 57 \} 1197 \> 25137})
+       (apply +)))
+;; => 216297
+
+(def part2
+  (->> corrupted
+       (map reverse)
+       (map (partial map {\( 1 \[ 2 \{ 3 \< 4}))
+       (map (partial reduce #(+ (* %1 5) %2) 0))
+       sort
+       (#(nth % (bit-shift-right (count corrupted) 1)))))
+;; => 2165057169