#include<fstream>
#define NMAx 20
#define _inf -1<<31
using namespace std;
int n,m,best,v[NMAx][NMAx];

void back() {
	int i,j,comb,lSum,cSum;
	for(comb=0;comb<(1<<n);comb++) {
		cSum=0;
		for(j=0;j<m;j++) {
			lSum=0;
			for(i=0;i<n;i++)
				if((1<<i) & comb)
					lSum+=v[i][j];
				else
					lSum-=v[i][j];
			if(lSum<0)
				cSum-=lSum;
			else
				cSum+=lSum;
			}
		if(cSum>best)
			best=cSum;
		}
}
void citire() {
	int i,j;
	ifstream in("flip.in");
	in>>n>>m;
	for(i=0;i<n;i++)
		for(j=0;j<m;j++)
			in>>v[i][j];
	in.close();
}
void afis() {
	ofstream out("flip.out");
	out<<best<<'\n';
	out.close();
}
int main() {
	citire();
	best=_inf;
	back();
	afis();
	return 0;
}