#include<stdio.h>
#include<iostream.h>
int n,m,flip[16];
long matrice[16][16] ;
long long sumamax=0,suma,b;
void flipit()
{
	suma=0;
	int i,j;
	for(i=0;i<n;i++)
	{
		b=0;
			for(j=0;j<m;j++)
		 		b+=matrice[i][j]*flip[j];
		if(b<0)
			suma+= -1*b;			
		else
			 suma+=b;
	}
	if(sumamax<suma)
		sumamax=suma;
}
void back(int cont)
{
	if(cont==m)		
		flipit();
	flip[cont]=1; back(cont+1);
	flip[cont]=-1; back(cont+1);
}
main()
{
	int i,j;
	freopen("flip.in","r",stdin);
	freopen("flip.out","w",stdout);
	cin>>n>>m;
	for(i=0;i<n;i++)
		for(j=0;j<m;j++)
			cin>>matrice[i][j];
	back(0);
	cout<<sumamax<<"\n";
}