#include<stdio.h>
#include<algorithm>
using namespace std;
int m,n,a[17][17],v[27],maxim;
void back(int k)
{
	int i,j;
	if (k==m+1)
	{
		int s;
		s=0;
		for (i=1;i<=n;i++)
		{
			int sum;
			sum=0;
			for (j=1;j<=k-1;j++)
				sum+=a[i][j]*v[j];
			if (sum<0)
				sum*=(-1);
			s+=sum;
		}
		maxim=max(maxim,s);
	}
	else
	{
		v[k]=1;
		back(k+1);
		v[k]=-1;
		back(k+1);
	}
}
int main()
{
    freopen("flip.in","r",stdin);
    freopen("flip.out","w",stdout);
	int i,j;
	scanf("%d%d",&n,&m);
	for (i=1;i<=n;i++)
		for (j=1;j<=m;j++)
			scanf("%d",&a[i][j]);
	back(0);
	printf("%d",maxim);
}