import Control.Monad

myfold (a:as) (b:bs) =
  a*b + myfold as bs
myfold [] [] = 0


main = do
  [n, m, c] <- (map read) . words <$> getLine
  b <- (map read) . words <$> getLine
  a <- replicateM n ((map read . words) <$> getLine)
  let 
    ret = length $ filter (\l -> myfold b l + c > 0) a
  putStrLn $ show ret
