start day 19

.gitignore

@@ -1,4 +1,4 @@
-*/target/
+target/
 */.vscode/
 
 

2024/src/day19.clj

@@ -0,0 +1,85 @@
+(ns day19
+  (:require
+   [clojure.string :as str] ; [core :as c]
+   input-manager
+   [orchard.pp :as pp]))
+
+(def sample-input "r, wr, b, g, bwu, rb, gb, br
+
+brwrr
+bggr
+gbbr
+rrbgbr
+ubwu
+bwurrg
+brgr
+bbrgwb")
+
+(let [[w _ & p]
+      #_(str/split-lines sample-input)
+      (input-manager/get-input 2024 19)]
+  (def words (into #{} (str/split w #", ")))
+  (def puzzles p)
+  (def word-sizes (->> words
+                       (map count)
+                       distinct
+                       sort
+                       reverse)))
+
+(defn p [x]
+  (println x)
+  x)
+
+(defn next-search-index [puzzle searched valid-subsets]
+  (if (every? (complement true?) searched)
+    0
+    (some->> valid-subsets
+             (map-indexed vector)
+             (filter second)
+             (filter (fn [[idx :as el]]
+                       (not (searched (inc idx)))))
+             last
+             first
+             inc)))
+
+(defn find-valid-subsets [puzzle search-idx valid-subsets]
+  (let [max-idx (count puzzle)]
+    (->> word-sizes
+         (map (partial + search-idx)) ; get end pos
+         (filter #(<= % max-idx))
+         (map (partial subs puzzle search-idx)) ;get substrings
+         (filter words)
+         (map (comp (partial + search-idx) dec count))
+         (reduce (fn [acc idx]
+                   (assoc acc idx true))
+                 valid-subsets))))
+
+(defn is-valid
+  ([puzzle]
+   (is-valid puzzle
+             (mapv (constantly false) puzzle)
+             (mapv (constantly false) puzzle)
+             0))
+  ([puzzle searched valid-subsets n]
+   (let [search-idx (next-search-index puzzle searched valid-subsets)]
+     (cond
+       (or (not search-idx)
+           (= search-idx -1))
+       false
+
+       (>= search-idx (count puzzle))
+       true
+
+       :else
+       (let [next-subsets (find-valid-subsets puzzle search-idx valid-subsets)]
+         (if (last next-subsets)
+           true
+           (recur puzzle
+                  (assoc searched search-idx true)
+                  next-subsets
+                  (inc n))))))))
+
+(->> puzzles
+     (map is-valid)
+     (filter identity)
+     count)