#include <stdio.h>
#include <algorithm>

using namespace std;

int n,m;
int a[32][32];
int st[32];
int best = -3143554;


void back(int k)
{
	if ( k == n)
	{
		int sum = 0;
		for (int j = 0 ; j < m ; ++j)
		{
			int sumc = 0;
			for (int i = 0 ; i < n ; ++i)
				sumc += a[i][j] * st[i];

			sum += abs(sumc);
		}
		best = max(sum,best);
	}
	else for (int i = 0 ; i < 2 ; ++i)
	{
		st[k] = -1 + i*2;
		back(k+1);
	}
}

int main()
{
	freopen("flip.in","r",stdin);
	freopen("flip.out","w",stdout);
	scanf("%d%d",&n,&m);
	
	for (int i = 0 ; i < n ; ++i)
		for (int j = 0 ; j < m ; ++j)
			scanf("%d",&a[i][j]);

	back(0);
	printf("%d\n",best);

	return 0;
}