Day 07: Solve part 1 and 2

src/advent_of_code_2023/day07.clj

@@ -1,9 +1,104 @@
 (ns advent-of-code-2023.day07
   (:require
+   [clojure.string :as string]
    [advent-of-code-2023.utils.string :as u]))
 
-(defn parse-input [input])
+(defn- hand-type [freqs]
+  (condp = (sort (vals freqs))
+    [5] :five-of-a-kind
+    [1 4] :four-of-a-kind
+    [2 3] :full-house
+    [1 1 3] :three-of-a-kind
+    [1 2 2] :two-pair
+    [1 1 1 2] :one-pair
+    :high-card))
 
-(defn day07-1 [parsed-input])
+(defn parse-input [input]
+  (transduce
+   (comp
+    (remove #(some string/blank? %))
+    (map (fn [[hand bid]]
+           (let [freqs (frequencies hand)]
+             {:hand hand
+              :bid (Long/parseLong bid)
+              :frequencies freqs
+              :type (hand-type freqs)}))))
+   conj [] (u/split-pairs input)))
 
-(defn day07-2 [parsed-input])
+(defonce ^:private hand-type-ranking
+  {:five-of-a-kind 6
+   :four-of-a-kind 5
+   :full-house 4
+   :three-of-a-kind 3
+   :two-pair 2
+   :one-pair 1
+   :high-card 0})
+
+(defonce ^:private card-ranking
+  {\A 12
+   \K 11
+   \Q 10
+   \J 9
+   \T 8
+   \9 7
+   \8 6
+   \7 5
+   \6 4
+   \5 3
+   \4 2
+   \3 1
+   \2 0})
+
+(defn- hand-comp [[^long t1 & h1 :as c1] [^long t2 & h2]]
+  (cond
+    (nil? c1) 0
+    (< t1 t2) -1
+    (> t1 t2) 1
+    :else (recur h1 h2)))
+
+(defn- day07 [hands sort-fn]
+  (transduce
+   (map-indexed (fn [^long rank {:keys [^long bid]}]
+                  (* (inc rank) bid)))
+   + (sort-by sort-fn hand-comp hands)))
+
+(defn day07-1 [hands]
+  (day07 hands
+         (fn [{:keys [type hand]}]
+           (conj (map card-ranking hand)
+                 (hand-type-ranking type)))))
+
+(defonce ^:private joker-card-ranking
+  {\A 12
+   \K 11
+   \Q 10
+   \T 9
+   \9 8
+   \8 7
+   \7 6
+   \6 5
+   \5 4
+   \4 3
+   \3 2
+   \2 1
+   \J 0})
+
+(defonce ^:private joker-hand
+  {[:four-of-a-kind 4] :five-of-a-kind
+   [:four-of-a-kind 1] :five-of-a-kind
+   [:full-house 3] :five-of-a-kind
+   [:full-house 2] :five-of-a-kind
+   [:three-of-a-kind 3] :four-of-a-kind
+   [:three-of-a-kind 1] :four-of-a-kind
+   [:two-pair 2] :four-of-a-kind
+   [:two-pair 1] :full-house
+   [:one-pair 2] :three-of-a-kind
+   [:one-pair 1] :three-of-a-kind
+   [:high-card 1] :one-pair})
+
+(defn day07-2 [hands]
+  (day07 hands
+         (fn [{:keys [type hand frequencies]}]
+           (conj (map joker-card-ranking hand)
+                 (hand-type-ranking (get joker-hand [type (frequencies \J)]
+                                         type))))))

test/advent_of_code_2023/day07_test.clj

@@ -4,26 +4,26 @@
    [advent-of-code-2023.day07 :refer :all]
    [advent-of-code-2023.test-utils :as tu]))
 
-(def ^:private example-input (parse-input ""))
+(def ^:private example-input (parse-input "32T3K 765
+T55J5 684
+KK677 28
+KTJJT 220
+QQQJA 483"))
 
 (def ^:private input (parse-input (tu/slurp-input "resources/day07.txt")))
 
 (deftest day07-1-example-test
   (testing "day07-1 example"
-    (is (= nil
-           (day07-1 example-input)))))
+    (is (= 6440 (day07-1 example-input)))))
 
 (deftest day07-1-test
   (testing "day07-1"
-    (is (= nil
-           (day07-1 input)))))
+    (is (= 246163188 (day07-1 input)))))
 
 (deftest day07-2-example-test
   (testing "day07-2 example"
-    (is (= nil
-           (day07-2 example-input)))))
+    (is (= 5905 (day07-2 example-input)))))
 
 (deftest day07-2-test
   (testing "day07-2"
-    (is (= nil
-           (day07-2 input)))))
+    (is (= 245794069 (day07-2 input)))))