#include<fstream>
#include<cmath>
using namespace std;
ifstream f("flip.in");
ofstream g("flip.out");
int i,j,n,m,smax,s,v1[20],v[20],a[20][20];
int main()
{f>>n>>m;
for(i=1;i<=n;++i)
	for(j=1;j<=m;++j)
		f>>a[i][j];
smax=0;
while(1)
{i=1;
while(v[i]==1)
	v[i]=0,++i;
if(i>n)
	break;
v[i]=1;
for(i=1;i<=m;++i)
	v1[i]=0;
for(i=1;i<=m;++i)
	for(j=1;j<=n;++j)
		if(v[j]==1)
			v1[i]=v1[i]-a[j][i];
		else
			v1[i]=v1[i]+a[j][i];
s=0;
for(i=1;i<=m;++i)
	if(v1[i]>0)
		s=s+v1[i];
	else
		s=s-v1[i];
if(smax<s)
	smax=s;
}
g<<smax<<'\n';
return 0;
}