#include <fstream>
#include <climits>

using namespace std;
ifstream f("flip.in");
ofstream g("flip.out");
int v[20], n, i, j, s, sp, a[20][20], m, maxi=INT_MIN;

int main()
{
	f>>n>>m;
	for ( i=1; i <= n; i++ ) for ( j=1; j <= m; j++) f >> a[i][j];
	while ( v[0] == 0 ){
		i=n;
		while ( v[i] == 1 ) v[i]=0, i--;
		v[i]=1;
		s=0;
		for ( j=1; j <= m; j++ ){
			sp=0;
			for ( i=1; i <= n; i++ )
				if ( v[i] == 1 ) sp -= a[i][j];
				else sp += a[i][j];
			s += max ( sp, -sp );
		}
		if ( s > maxi ) maxi = s;
	}
	g << maxi;
	return 0;
}