import qualified Data.Text as T
import qualified Data.Text.IO as T
import qualified Data.Text.Read as T

main :: IO ()
main = do
  xs <- map unsafeTextToInt . T.words <$> T.getLine :: IO [Int]
  print . fst . head . filter ((== 0) . snd) . zip [1..] $ xs

unsafeTextToInt :: T.Text -> Int
unsafeTextToInt s = case T.signed T.decimal s of
  Right (n, _) -> n
{-# INLINE unsafeTextToInt #-}
