1 files changed, 33 insertions, 0 deletions
diff --git a/year2021/day13/part2.clj b/year2021/day13/part2.clj
new file mode 100644
index 0000000..6db6555
--- /dev/null
+++ b/year2021/day13/part2.clj
@@ -0,0 +1,33 @@
+(require '[clojure.string :as str])
+
+(def input (->> (slurp "./in")
+                (str/split-lines)
+                (split-with not-empty)
+                ((juxt
+                  (fn [lst]
+                    (reduce
+                      #(conj %1 (mapv read-string (str/split %2 #",")))
+                      #{} (first lst)))
+                  (fn [lst]
+                    (->> (rest (second lst))
+                         (map #(-> %
+                                   (str/split #"=")
+                                   (update 0 (comp {\x 0 \y 1} last))
+                                   (update 1 read-string)))
+                         ))))))
+
+(defn print-grid [pts]
+  (doseq [p pts] (println (str/join [(first p) "," (second p)]))))
+
+(defn fold-point [idx chg pt]
+  (cond-> pt (> (get pt idx) chg) (update idx #(- % (* 2 (- % chg))))))
+
+(print-grid
+  (apply
+    (partial
+      reduce
+      #(let [ins (first %2)]
+         (set (map (partial fold-point (first %2) (second %2)) %1))))
+    input
+    ))
+