#include<stdio.h>
int n,m,max=-2000000000;
int v[20][20];
int st[20];

void read()
{
	freopen("flip.in","r",stdin);
	freopen("flip.out","w",stdout);
	scanf("%d%d",&n,&m);
	int i,j;
	for(i=1;i<=n;i++)
		for(j=1;j<=m;j++)
			scanf("%d",&v[i][j]);
}

void rez()
{
	int i,j,s=0,s1;
	for(i=1;i<=n;i++)
	{
		s1=0;
		for(j=1;j<=m;j++)
			s1=s1+v[i][j]*st[j];
		if(s1>=0)
			s=s+s1;
		else
			s=s-s1;
	}
	if(s>max)
		max=s;
}

void back(int k)
{
	if(k==m+1)
	{
		rez();
		return;
	}
	st[k]=1;
	back(k+1);
	st[k]=-1;
	back(k+1);
}

int main()
{
	read();
	back(1);
	printf("%d",max);
	return 0;
}