import Control.Applicative
import Control.Monad
import System.IO
import Data.List

down_check :: [[Int]] -> Int -> Int -> Int -> Int
right_check :: [[Int]] -> Int -> Int -> Int -> Int
diag_check :: [[Int]] -> Int -> Int -> Int -> Int
ldiag_check :: [[Int]] -> Int -> Int -> Int 
rdiag_check :: [[Int]] -> Int -> Int -> Int 

down_check gridL max x y
    | x > 16 = max
    | y > 19 = down_check gridL max (x+1) 0
    | product [gridL !! x !! y, gridL !! (x+1) !! y, 
               gridL !! (x+2) !! y, gridL !! (x+3) !! y] 
      > max = 
            down_check 
                gridL 
                (product [gridL !! x !! y, gridL !! (x+1) !! y, 
                          gridL !! (x+2) !! y, gridL !! (x+3) !! y]) 
                x (y+1)
    | otherwise = down_check gridL max x (y+1)

right_check gridL max x y
    | x > 19 = max
    | y > 16 = right_check gridL max (x+1) 0
    | product [gridL !! x !! y, gridL !! x !! (y+1), 
               gridL !! x !! (y+2), gridL !! x !! (y+3)] 
      > max = 
            right_check 
                gridL 
                (product [gridL !! x !! y, gridL !! x !! (y+1), 
                          gridL !! x !! (y+2), gridL !! x !! (y+3)]) 
                x (y+1)
    | otherwise = right_check gridL max x (y+1)
    
diag_check gridL max x y
    | x > 16 = max
    | y > 19 = diag_check gridL max (x+1) 0
    | maximum [ldiag_check gridL x y, rdiag_check gridL x y] > max = 
            diag_check 
                gridL 
                (maximum [ldiag_check gridL x y, rdiag_check gridL x y]) 
                x 
                (y+1)
    | otherwise = diag_check gridL max x (y+1)
    
ldiag_check gridL x 0 = 0
ldiag_check gridL x 1 = 0
ldiag_check gridL x 2 = 0
ldiag_check gridL x 3 = 0
ldiag_check gridL x y = product [gridL !! x !! y, gridL !! (x+1) !! (y-1),
                                 gridL !! (x+2) !! (y-2), gridL !! (x+3) !! (y-3)]

rdiag_check gridL x 16 = 0
rdiag_check gridL x 17 = 0
rdiag_check gridL x 18 = 0
rdiag_check gridL x 19 = 0
rdiag_check gridL x y = product [gridL !! x !! y, gridL !! (x+1) !! (y+1),
                                 gridL !! (x+2) !! (y+2), gridL !! (x+3) !! (y+3)]

main :: IO ()
main = do
    grid_temp <- getMultipleLines 20
    let grid = map ( map ( read :: String -> Int ) . words ) grid_temp
    let down_max = down_check grid 0 0 0
    let right_max = right_check grid 0 0 0
    let diag_max = diag_check grid 0 0 0
    print (maximum [down_max, right_max, diag_max])

getMultipleLines :: Int -> IO [String]

getMultipleLines n
    | n <= 0 = return []
    | otherwise = do          
        x <- getLine         
        xs <- getMultipleLines (n-1)    
        let ret = (x:xs)    
        return ret