move 2021 days to folder; update README

1 files changed, 15 insertions, 0 deletions

diff --git a/year2021/day1/part1.clj b/year2021/day1/part1.clj
new file mode 100644
index 0000000..1c2c756
--- /dev/null
+++ b/year2021/day1/part1.clj
@@ -0,0 +1,15 @@
+; Day 1, part 1
+; Read a list of numbers from stdin, separated by newlines.
+; Count occurances of the current number being greater than
+; the previous.
+;
+
+(as-> (slurp "./in") $
+     (clojure.string/split-lines $)
+     (map read-string $)
+     (reduce
+       #(cond-> (assoc %1 0 %2) (> %2 (first %1)) (update 1 inc))
+       [(first $) 0]
+       (rest $))
+     (println (second $)))
+