#include<stdio.h>
using namespace std;

int a[20][20],n,m;
int sign[20],smax;

FILE *in=fopen("flip.in","r"),*out=fopen("flip.out","w");

void check()
{
	int i,j,s,suma=0;
	for(j=1;j<=m;++j)
	{
		s=0;
		for(i=1;i<=n;++i)
		{
			s+=sign[i]*a[i][j];
		}
		if(s<0)
			s*=-1;
		suma+=s;
	}
	if(smax<suma)
		smax=suma;
}
void bkt(int pas)
{
	if(pas==n+1)
		check();
	else
	{
		sign[pas]=1;
		bkt(pas+1);
		sign[pas]=-1;
		bkt(pas+1);
	}
}
int main()
{
	int i,j;
	fscanf(in,"%d %d",&n,&m);
	for(i=1;i<=n;++i)
		for(j=1;j<=m;++j)
			fscanf(in,"%d",&a[i][j]);
	bkt(1);
	fprintf(out,"%d\n",smax);
	return 0;
}