import math as mp
import numpy
cin = open("flip.in", "r")
cout = open("flip.out", "w")

def parser():
    while 1:
        data = list(cin.read().split())
        for number in data:
            if len(number) > 0:
                yield(number)   

input_parser = parser()

def get_word():
    global input_parser
    return next(input_parser)

# numpy and scipy are available for use
import numpy
import scipy


n = get_word()
m = get_word()

n = int(n)
m = int(m)

a = numpy.zeros((n, m))
for i in range(0, n):
	for j in range(0, m):
	   a[i][j] = get_word()
	 

best = int(-(10**13))
for conf in range(0, 2**m):
    conf_cost = 0
    for i in range(0, n):
        sum1 = 0
        sum2 = 0
        for j in range(0, m):
           if (conf >> j) & 1:
             sum1 = sum1 + a[i][j]
             sum2 = sum2 - a[i][j]
           else:
               sum1 = sum1 - a[i][j]
               sum2 = sum2 + a[i][j]
     
        conf_cost = conf_cost + max(sum1, sum2)
    best = max(best, conf_cost)
    
print(int(best))