Add 2015 day 8

haskellAoC/src/Y2015/Day08.hs

@@ -0,0 +1,29 @@
+module Y2015.Day08 (y15day08) where
+
+import Data.List
+
+decodeStr :: String -> String
+decodeStr = dropFirstLast . removeStuff
+  where dropFirstLast = tail . init
+        removeStuff s@(h:t)
+          | "\\x" `isPrefixOf` s  = removeStuff (drop 3 s)
+          | "\\\\" `isPrefixOf` s = h:(removeStuff (drop 1 t))
+          | "\\" `isPrefixOf` s   = removeStuff t
+          | otherwise             = h:(removeStuff t)
+        removeStuff ""            = ""
+
+encodeStr :: String -> String
+encodeStr input = "\"" ++ (encode' input) ++ "\""
+  where encode' (h:t)
+          | h == '\\' = "\\\\" ++ (encode' t)
+          | h == '"' = "\\\"" ++ (encode' t)
+          | otherwise = h:(encode' t)
+        encode' "" = ""
+
+y15day08 :: [String] -> (String, String)
+y15day08 input = (part1, part2)
+  where part1 = show $ (raw_length - decoded_length)
+        part2 = show $ (encoded_length - raw_length)
+        decoded_length = sum $ map (length . decodeStr) input
+        encoded_length = sum $ map (length . encodeStr) input
+        raw_length = sum $ map length input

haskellAoC/src/Y2015/Days.hs

@@ -7,6 +7,7 @@ import Y2015.Day04
 import Y2015.Day05
 import Y2015.Day06
 import Y2015.Day07
+import Y2015.Day08
 
 year2015 :: String -> [String] -> (String, String)
 year2015 "01" = y15day01
@@ -16,3 +17,4 @@ year2015 "04" = y15day04
 year2015 "05" = y15day05
 year2015 "06" = y15day06
 year2015 "07" = y15day07
+year2015 "08" = y15day08