module Main where

import Data.Vector.Unboxed (generate,(!),Vector(..),ifilter)
import qualified Data.Vector.Unboxed as V

import qualified Data.List as L

import Data.Sequence

import Data.Vector.Strategies

import Control.Monad as C

main :: IO ()
main = do

  s <- forM [0..199] $ \e -> do
            let delta = e `mod` 2

            let x = V.enumFromStepN delta 1 1000000
            let y = V.unfoldr ( \i -> if i < (1000000-1) then ( Just (x!i + x!(i+1), i+1)  ) else Nothing) 0
            let z = V.sum (ifilter (\i _ -> i `mod` 100 == 0) y)
            return z

  print $ (sum s) `div` (200 :: Int)