#include<cstdio>
#include<fstream>
#include<iostream>

using namespace std;

#define nn 17

int a[nn][nn],v[nn],ss[nn];
int n,m,s,sum;

void sol ()
{

for(int i=1;i<=n;++i)
for(int j=1;j<=m;++j)
if(v[i]==1)
ss[j]+=(a[i][j]*(-1));
else
ss[j]+=a[i][j];
for(int i=1;i<=m;++i){
	
if(ss[i]<0)
ss[i]*=(-1);
sum+=ss[i];
	
}
	
if(sum>s)
s=sum;

for(int i=1;i<=m;++i)
ss[i]=0;

sum=0;

}

void back	(int p)
{

int i;

for(i=0;i<=1;++i){

v[p]=i;
if(p==n)
sol();
else
back(p+1);	

}	
	
}

int main ()
{

ifstream fin ("flip.in");
freopen("flip.out","w",stdout);
fin>>n>>m;
for(int i=1;i<=n;++i)
for(int j=1;j<=m;++j)
fin>>a[i][j];
fin.close();

back(1);

printf("%d\n",s);

return 0;}