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module Main where
import Memo2 ( memo )
import Data.List ( genericLength, genericReplicate )
import System.Environment ( getArgs )
main :: IO ()
main = do (arg:_) <- getArgs
mapM_ printTriple [ (i,fib i,mfib i) | i <- [10..read arg] ]
where printTriple (i,fi,mfi) = do print i
print fi
print mfi
putStrLn ""
-- There is not much point in memoising Integers, so we use unary "numbers" instead
mfib :: Integer -> Integer
mfib = genericLength . mfib' . flip genericReplicate ()
mfib' :: [()] -> [()]
mfib' = memo ufib
ufib :: [()] -> [()]
ufib [] = [()]
ufib [()] = [()]
ufib (():n1@(():n2)) = mfib' n1 ++ mfib' n2
fib :: Integer -> Integer
fib 0 = 1
fib 1 = 1
fib n = fib (n-1) + fib (n-2)
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