import Numeric
import Data.Char
import Control.Monad

intToChar :: Int -> Char
intToChar x
    |  0 <= x && x <=  9 = chr $ ord '0' + x
    | 10 <= x && x <= 35 = chr $ ord 'A' - 10 + x
    
charToInt :: Char -> Int
charToInt c
    | '0' <= c && c <= '9' = ord c - ord '0'
    | 'A' <= c && c <= 'Z' = ord c - ord 'A' + 10

toDecimal :: Integral a => Int -> String -> a
toDecimal fr fx = sum $ zipWith (\a b -> a * fr' ^ b) fx' $ reverse [0..length fx' - 1]
    where
        fx' = dropWhile (== 0) $ map (fromIntegral . charToInt) fx
        fr' = fromIntegral fr

solve :: Integral a => [String] -> a
solve xs = minimum $ zipWith toDecimal minrs xs
    where
        minrs = map ((+ 1) . charToInt . maximum) xs

main = do
    n <- readLn
    vs <- replicateM n getLine
    print $ solve vs