1 files changed, 72 insertions, 0 deletions
diff --git a/Haskell-book/08/src/Exercises.purs b/Haskell-book/08/src/Exercises.purs
new file mode 100644
index 0000000..12460a8
--- /dev/null
+++ b/Haskell-book/08/src/Exercises.purs
@@ -0,0 +1,72 @@
+module Exercises where
+    
+import Data.Tuple (Tuple(..), fst, snd)
+import Prelude
+
+--
+-- Reviewing currying
+--
+cattyConny :: String -> String -> String
+cattyConny x y = x <> " mrow " <> y
+
+flippy :: String -> String -> String
+flippy = flip cattyConny
+
+appedCatty :: String -> String
+appedCatty = cattyConny "woops"
+
+frappe :: String -> String
+frappe = flippy "haha"
+
+--
+-- Recursion
+--
+-- Exercise 2
+sumNumbers :: Int -> Int
+sumNumbers x = sumNumbers' x 0
+    where sumNumbers' 0 acc = 0
+          sumNumbers' n acc = n + (sumNumbers' (n - 1) acc)
+
+-- Exercise 2
+multiply :: Int -> Int -> Int
+multiply _ 0 = 0
+multiply x 1 = x
+multiply x y = x + multiply x (y - 1)
+
+--
+-- Fixing dividedBy
+--
+data DividedResult =
+      Result Int
+    | DividedByZero
+
+instance showDividedResult :: Show DividedResult where
+    show :: DividedResult -> String
+    show (Result n)    = show n
+    show DividedByZero = show "Divided by zero"
+
+go :: Int -> Int -> Int -> Tuple Int Int
+go n d count
+    | n < d     = Tuple count n
+    | otherwise = go (n - d) d (count + 1)
+
+abs :: Int -> Int
+abs x
+    | x < 0     = -x
+    | otherwise = x
+
+dividedBy :: Int -> Int -> Tuple DividedResult DividedResult
+dividedBy num denom
+    | denom == 0        = Tuple DividedByZero DividedByZero
+    | (num * denom) < 0 = let tuple = go (abs num) (abs denom) 0 in
+                                Tuple (Result (-(fst tuple))) (Result (snd tuple))
+    | otherwise         = let tuple = go (abs num) (abs denom) 0 in
+                                Tuple (Result (fst tuple)) (Result (snd tuple))
+
+--
+-- McCarthy 91 function
+--
+mc91 :: Int -> Int
+mc91 n
+    | n > 100   = n - 10
+    | otherwise = mc91 (mc91 (n + 11))