import Control.Monad (replicateM)
import Data.List (elemIndex)
import Data.Maybe (fromJust)

transpose :: [[a]] -> [[a]]
transpose ([]:_) = []
transpose xs = map head xs : transpose (map tail xs)

solve :: [[String]] -> Int
solve ns
    | isrentyon = succ $ fromJust $ elemIndex True r
    | otherwise = -1
    where
        r = map (all f) ys
        f s = s == "nyanpass" || s == "-"
        ys = transpose ns
        isrentyon = (length . filter (==True)) r == 1

main = do
    n <- readLn
    ns <- map words <$> replicateM n getLine
    print $ solve ns