move 2021 days to folder; update README

1 files changed, 20 insertions, 0 deletions

diff --git a/year2021/day7/part2.clj b/year2021/day7/part2.clj
new file mode 100644
index 0000000..b96b55d
--- /dev/null
+++ b/year2021/day7/part2.clj
@@ -0,0 +1,20 @@
+(defn calc-fuel [lst pos]
+  (reduce #(as-> %2 $
+             (- pos $)
+             (Math/abs $)
+             (/ (* $ (inc $)) 2)
+             (+ %1 $)
+             )
+          0 lst
+          )
+  )
+
+(let [input (as-> (slurp "./in") $ ;"16,1,2,0,4,2,7,1,2,14"
+                  (clojure.string/split $ #",")
+                  (map read-string $)
+                  )
+      mean (quot (apply + input) (count input))]
+  (println (min (calc-fuel input mean)
+                (calc-fuel input (inc mean))))
+  )
+