Day 3 - clojure

README.md

@@ -6,7 +6,8 @@
   - [Day 0](./day-0)
 - [x] C
   - [Day 1](./day-1)
-- [] Clojure
+- [x] Clojure
+  - [Day 2](./day-2)
 - [] Common LISP
 - [] C++
 - [] Dart

day-02/sol.clj

@@ -0,0 +1,34 @@
+(require '[clojure.java.io])
+
+(defn find-recurring-characters [strs]
+  (reduce (fn [a x]
+            (into #{} (filter #(contains? a %) x)))
+          (into #{} (first strs))
+          strs))
+
+(defn get-priority [c]
+  (if (>= c 97)
+    (- c 96)
+    (- c 38)))
+
+(defn obtain-total-priorities [rucksacks]
+  (reduce + (map (fn [line]
+                   (let [half (/ (count line) 2)]
+                     (get-priority (int
+                                    (first (find-recurring-characters
+                                            (list (subs line 0 half)
+                                                  (subs line half))))))))
+                 rucksacks)))
+
+(defn obtain-total-priorities-2 [rucksacks]
+  (reduce + (map (fn [lines]
+                   (get-priority (int (first (find-recurring-characters lines)))))
+                 (partition 3 rucksacks))))
+
+(defn main []
+  (with-open [rdr (clojure.java.io/reader "input")]
+    (println (obtain-total-priorities (line-seq rdr))))
+  (with-open [rdr (clojure.java.io/reader "input")]
+    (println (obtain-total-priorities-2 (line-seq rdr))))
+  (System/exit 0))
+(main)