#include<fstream.h>
ifstream f("flip.in");
ofstream g("flip.out");
int a[17][17],s,t,x=1,max;
short n,m,b[18];
void citire()
{f>>n>>m;
 for(short i=1;i<=n;i++)
	 for(short j=1;j<=m;j++)
		 f>>a[i][j];
}
void adun()
{short i=1;
 while(b[i])
	b[i++]=0;
 b[i]++;
}
void sume()
{for(short i=1;i<=n;i++)
	{s=0;
	 for(short j=1;j<=m;j++)
		 if(b[j])
			 s+=a[i][j];
		 else
			 s-=a[i][j];
	 if(s<0)
		 t-=s;
	 else
		 t+=s;
	}
 if(t>max)
	 max=t;
}
int main()
{
citire();
int i;
for(i=1;i<=m;i++)
 x*=2;
for(i=1;i<=x;i++)
{t=0;
 sume();
 adun();
}
g<<max;
return 0;
}