From 1dd8c83ee6ca479d912606f20da4176893cfd0bb Mon Sep 17 00:00:00 2001 From: Xavier Morel Date: Mon, 2 Dec 2019 09:18:11 +0100 Subject: [PATCH] Add 2015 day 1 --- 2015/day1.hs | 12 ++++++++++++ 1 file changed, 12 insertions(+) create mode 100644 2015/day1.hs diff --git a/2015/day1.hs b/2015/day1.hs new file mode 100644 index 0000000..60a85f7 --- /dev/null +++ b/2015/day1.hs @@ -0,0 +1,12 @@ +import Data.List + +day1steps :: [Char] -> [Int] +day1steps xs = [if x == '(' then 1 else -1 | x <- xs] + +day1p1 :: [Char] -> Int +day1p1 xs = sum(day1steps xs) + +day1p2 :: [Char] -> Maybe Int +day1p2 xs = findIndex (== entrance) steps + where steps = scanl (\acc x -> acc + x) 0 (day1steps xs) + entrance = -1