diff options
Diffstat (limited to 'Puzzle1.hs')
-rw-r--r-- | Puzzle1.hs | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/Puzzle1.hs b/Puzzle1.hs new file mode 100644 index 0000000..dc39b61 --- /dev/null +++ b/Puzzle1.hs @@ -0,0 +1,25 @@ +import Data.Char (digitToInt) + +solve1 :: [Char] -> Int +solve1 xs = let ys = digitToInt <$> xs in firstAndLast ys + solve' ys + +solve' :: [Int] -> Int +solve' [] = 0 +solve' [x] = 0 +solve' (x:y:xs) = if x == y then x + solve' (y:xs) else solve' (y:xs) + +firstAndLast :: [Int] -> Int +firstAndLast [] = 0 +firstAndLast [x] = 0 +firstAndLast xs = if head xs == last xs then head xs else 0 + +splitInput :: [Int] -> ([Int], [Int]) +splitInput xs = splitAt (length xs `div` 2) xs + +sumSame :: ([Int], [Int]) -> Int +sumSame ([], _) = 0 +sumSame (_, []) = 0 +sumSame (x:xs, y:ys) = if x == y then x * 2 + sumSame (xs, ys) else sumSame (xs, ys) + +solve2 :: [Char] -> Int +solve2 xs = sumSame $ splitInput $ digitToInt <$> xs |