import Control.Monad (replicateM)
import Data.List     (permutations)

getPoint l (x:y:zs)
    | filter (\a -> x==a||y==a) l == [x,y] = head zs
    | otherwise                            = 0

main = do
    n:m:_     <- map read <$> words <$> getLine
    pointList <- replicateM m (map read <$> words <$> getLine)
    let lines   = permutations [0..(n-1)]
        results = map sum
            $ zipWith map (zipWith id (repeat getPoint) lines)
            $ repeat pointList
    print $ foldr max 0 results