-- Computes fibonacci numbers using memoization
-- by Scot Drysdale, 3/3/2008

module Fib where

import MemoS

fibHelper  :: MemoFunction Integer Integer
fibHelper n = 
  if n < 2 
  then return 1
  else do fm1 <- callMemo fibHelper (n-1)
          fm2 <- callMemo fibHelper (n-2)
          return (fm1 + fm2)
          
fib :: Integer -> Integer
fib n = runMemo fibHelper n