hw8: exercise 1 solutions

diff --git a/hw8/Party.hs b/hw8/Party.hs
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+{-# OPTIONS_GHC -Wall -fno-warn-orphans #-}
+module Party where
+
+import Data.Monoid
+import Employee
+
+-- exercise 1
+-- glCons - a naive way to add an employee to a guest list
+glCons :: Employee -> GuestList -> GuestList
+glCons e@(Emp {empFun = funval}) (GL els fun) = GL (e:els) (fun + funval)
+
+-- Monoid instance for GuestList
+instance Monoid GuestList where
+  mempty = GL [] 0
+  (GL el1 f1) `mappend` (GL el2 f2) = GL (el1 ++ el2) (f1 + f2)
+
+-- moreFun
+moreFun :: GuestList -> GuestList -> GuestList
+moreFun g1@(GL _ f1) g2@(GL _ f2) | f1 > f2 = g1
+                                  | otherwise = g2