#include<stdio.h>
int n,m,st[40];
long a[17][17],s;
FILE *f=fopen("flip.in","r");
FILE *g=fopen("flip.out","w");

void cit()
{
 fscanf(f,"%d%d",&n,&m);
  for(register int i=1;i<=n;i++)
	for(register int j=1;j<=m;j++)
	fscanf(f,"%ld",&a[i][j]);
	
}

void sol()
{
  long suma=0;
 long t[18][18];
  for(int j=1;j<=m;j++)
	{for(register int i=1;i<=n;i++)
	 {t[i][j]=a[i][j];
	 if(st[j]==2)
	 t[i][j]*=-1;
	 }}
  


 for(register int x=1;x<=n;x++)
 { long si=0;
  for(register int j=1;j<=m;j++)
   si+=t[x][j];
  if(si>0)
 suma+=si;
  else suma+=-si;
   }

 if(s<suma)
  s=suma;

}

void back(int k)
{
  if(k>m)
   sol();
else for(register int i=1;i<=2;i++)
  {st[k]=i;
   back(k+1);}
}

int main()
{
 cit();
 s=0;
 back(1);
 fprintf(g,"%ld",s);
 fcloseall();
 return 0;
}