main :: IO ()
main = do
  n <- readLn
  if n == 0
    then return ()
    else do
      ls <- getLine
      putStrLn $ solve ((map read . words) ls)
      main

solve :: [Int] -> String
solve ls
  | all (1 >= ) ls = "NA"
  | otherwise = show (1 + length (filter (0 /=) ls))