Day 1

diff --git a/src/day01.fnl b/src/day01.fnl
new file mode 100644 (file)
index 0000000..22dfe6f
--- /dev/null
+++ b/src/day01.fnl
@@ -0,0 +1,62 @@
+(module net.journcy.aoc2022.day01)
+
+(defn inc [n] (+ n 1))
+(defn dec [n] (- n 1))
+(defn lines [file] (icollect [v (io.lines file)] v))
+(defn numbers [file] (icollect [v (io.lines file)] (tonumber v)))
+(defn head [tbl] (. tbl 1))
+(defn last [tbl] (let [n (# tbl)] (. tbl n)))
+(defn map [f tbl] (icollect [_ v (ipairs tbl)] (f v)))
+(defn add [a b] (+ a b))
+(defn gt [a b] (> a b))
+(defn accnum [f tbl] 
+  (accumulate [acc 0
+               _ v (ipairs tbl)]
+    (f acc v)))
+(defn take [n tbl]
+  (accumulate [t []
+               i v (ipairs tbl)
+               &until (> i n)]
+    (doto t (table.insert v))))
+(defn partition [tbl brk]
+  (accumulate [parts [[]]
+               _ v (ipairs tbl)]
+    (do 
+      (if (= v brk)
+        (table.insert parts [])
+        (table.insert (last parts) v))
+      parts)))
+(defn sum [tbl] (accnum add tbl))
+(defn sort [tbl f] (do (table.sort tbl f) tbl))
+
+(comment
+  (partition [1 2 3 "" 4 5 6 "" 7 8 9] "")
+  (map sum [[1000 2000 3000]
+            [4000]
+            [5000 6000]
+            [7000 8000 9000]
+            [10000]])
+  (take 3 [[1000 2000 3000]
+            [4000]
+            [5000 6000]
+            [7000 8000 9000]
+            [10000]])
+  )
+
+
+(defn part1 [lines]
+  (->> (partition lines "")
+       (map (partial map tonumber))
+       (map sum)
+       (accnum math.max)))
+
+(defn part2 [lines]
+  (->> (partition lines "")
+      (map (partial map tonumber))
+      (map sum)
+      (#(sort $1 gt))
+      (take 3)
+      sum))
+
+(part1 (lines "input/day01.txt"))
+(part2 (lines "input/day01.txt"))