# include <stdio.h>

int n, m, i, j, sf = 0, v [ 10001 ], A[ 16 ][ 16 ];

void bestsum ( ){
	int i, j, sc = 0, st = 0;
	for ( i = 1; i <= n; i++ ){
		sc = 0;
		for ( j = 1; j <= m; j++ ) sc += ( A[ i ][ j ] * v[ j ] ); // inmultim cu posibilitatea Vj
		if ( sc < 0 ) sc = sc * -1; // daca Vj este -1, flipam linia/coloana
		st += sc;
	}
	if ( sf < st ) sf = st;
}

void backtrack ( int k ){
	if ( k > n ) bestsum ( ); // atunci cand am trecut prin toate posibilitatile si avem construit vectorul V
	else{
		for ( int i = -1; i <= 1; i += 2 ){
			v[k] = i; // vectorul de posibilitati/pozitii/combinari 
			backtrack ( k + 1 ); // apelare recurenta
		}
	}
}

int main(){
	freopen ("flip.in", "r", stdin);  freopen ("flip.out", "w", stdout);
	scanf ("%d%d", &n, &m); for ( i = 1; i <= n; i++ ) for ( j = 1; j <= m; j++ ) scanf ("%d", &A[ i ][ j ]);
	backtrack ( 1 ); // dam valoarea variabilei k = 1 pentru a incepe subprogramul backtrack 
	printf ("%d\n",sf);
	return 0;
}