{-# LANGUAGE BangPatterns #-}
import Data.List
import Data.Maybe
import Data.Function (fix)
import qualified Data.ByteString as BS
import qualified Data.ByteString.Char8 as BS8
 
getInts :: IO [Int]
getInts = (map parseInt . BS8.words) <$> BS.getLine 
    where parseInt = fst . fromJust . BS8.readInt

data Tree a = Tree (Tree a) a (Tree a)

instance Functor Tree where
    fmap f (Tree l m r) = Tree (fmap f l) (f m) (fmap f r)

index :: Tree a -> Int -> a
index (Tree _ m _) 0 = m
index (Tree l _ r) n = case (n -1) `divMod` 2 of
    (q,0) -> index l q
    (q,1) -> index r q

nats :: Tree Int
nats = go 0 1
    where go !n !s = Tree (go l s') n (go r s')
            where l = n + s
                  r = l + s
                  s' = s * 2

memo :: (Int -> a) -> (Int -> a)
memo f = index cached
    where cached = fmap f nats

memo2 :: (Int -> Int -> a) -> (Int -> Int -> a)
memo2 f = memo (\x -> memo (f x))

memo3 :: (Int -> Int -> Int -> a) -> (Int -> Int -> Int -> a)
memo3 f = memo (\x -> memo2 (f x))

{- dp example
fibo 0 = 0
fibo 1 = 1
fibo n = mfibo (n-1) + mfibo (n-2)

mfibo = memo f
-}


solve :: [Int] -> Int -> Integer
solve arr a = sum $ map f [1..n]
    where n = length arr
          f cnt = f' 0 cnt (cnt*a)
          f' idx cnt s
            | idx == n && (cnt == 0 && s == 0) = 1
            | idx == n = 0
            | otherwise = f'' (idx+1) cnt s + f'' (idx+1) (cnt-1) (s-(arr !! idx))
          f'' idx cnt s 
            | cnt < 0 || s < 0 = 0
            | otherwise = (memo3 f') idx cnt s

main :: IO ()
main = do
    [n, a] <- getInts
    arr <- getInts
    print (solve arr a)