diff options
Diffstat (limited to 'year2021/day15/part2.clj')
| -rw-r--r-- | year2021/day15/part2.clj | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/year2021/day15/part2.clj b/year2021/day15/part2.clj new file mode 100644 index 0000000..a422ed0 --- /dev/null +++ b/year2021/day15/part2.clj @@ -0,0 +1,41 @@ +(def input (->> (slurp "./in") + (clojure.string/split-lines) + (mapv (partial mapv (comp read-string str))) + (#(for [y (range 0 (count %)) x (range 0 (count (first %)))] + {[y x] (get-in % [y x])})) + (into {}) + ((fn [lst] + (reduce + #(into %1 + (for [j (range 0 5) i (range 0 5)] + {[(+ (first (key %2)) (* 100 j)) (+ (second (key %2)) (* 100 i))] + (let [s (+ i j (val %2))] (if (> s 9) (- s 9) s))})) + {} + lst + ))) + (into {}) + )) + +(def dim (apply max (map first (keys input)))) + +(defn find-neighbors [u] + (filter #(contains? input %) [(update u 0 inc) + (update u 0 dec) + (update u 1 inc) + (update u 1 dec)])) + +(loop [dist (zipmap (keys input) (repeat ##Inf)) + Q {[0 0] 0}] + (if (empty? Q) + (println (dist [dim dim])) + (let [[u distu] (first Q) + NN (reduce + #(let [dv (+ distu (input %2))] + (cond-> %1 + (> ((first %1) %2) dv) + (-> (update 0 assoc %2 dv) + (update 1 assoc %2 dv)))) + [dist {}] + (find-neighbors u))] + (recur (first NN) (sort-by val < (into (rest Q) (second NN))))))) + |