module Main where

import List
import System
import Char
import Int

main :: IO ()
main = do
         args <- getArgs
         case args of
           [n] -> do
	            putStrLn (show (matrixmult (atoi n)))
                    where atoi s = foldl (\a d -> 10*a+d) 0 (map digitToInt s)
           a   -> do
                    putStrLn "Need one argument."
                    exitWith (ExitFailure 1)

type Matrix k = [Row k]
type Row k    = [k]

genrow       :: Int -> Double -> Double -> [Double]
genrow n a d | n==0      = []
             | otherwise = [a] ++ genrow (n-1) (a+d) d

genmatrixpart     :: Int -> Int -> Matrix Double
genmatrixpart n m | n==m      = [genrow m ((fromInt n)+1.5) 1]
                  | otherwise = [genrow m ((fromInt n)+1.5) 1] ++ genmatrixpart (n+1) m

genmatrix n = genmatrixpart 1 n

matrixmultiply    :: Matrix Double -> Double
matrixmultiply a  =  sum (map sum [[row `dot` col | col<-a'] | row<-a])
              	     where v `dot` w = sum (zipWith (*) v w)
                           a'        = transpose a

matrixmult n = matrixmultiply (genmatrix n)