#include <iostream>
#include <fstream>
 
using namespace std;
ifstream fin("flip.in");
ofstream fout("flip.out");
int i,j,n,m,a[20][20], maxim=0, s[20];
 
 
void sum()
{
	int ss,st=0;
	for (i=1;i<=n;i++)
	{
		ss=0;
		for (j=1;j<=m;j++)
			ss+=s[j]*a[i][j];
		if (ss<0) st=st-ss;
			else st+=ss;
	}
	if (st>maxim) maxim=st;
	
}

void back(int k)
{
	int l;
	if (k>n) sum();
	else
	for (l=-1;l<=1;l++)
	if (l!=0) {s[k]=l;back(k+1);}
}

int main()
{
fin>>n>>m;
for(i=1;i<=n;i++)
for(j=1;j<=m;j++)
fin>>a[i][j];
back(1);
fout<<maxim;
fin.close();
fout.close();
return 0;
}