#include <stdio.h>

int N, M, T[16][16], max;

int main(){
	freopen("flip.in", "r", stdin);
	freopen("flip.out", "w", stdout);

	scanf("%d %d", &N, &M);

	for (int i = 0; i < N; ++i)
		for (int j = 0; j < M; ++j)
			scanf("%d", &T[i][j]),
			max += T[i][j];
	
	for (int i = 1; i < 1 << N; ++i){
		int maxx = 0;
		for (int r = 0; r < M; ++r){
			int in = 0, out = 0;
			for (int j = 0; j < N; ++j){
				if (i & (1 << j))
					in += T[j][r];
				else out += T[j][r];
			}
			if (in - out > -in + out)
				maxx += in - out;
			else maxx += -in + out;
		}
		if (maxx > max) max = maxx;
	}
	printf("%d", max);

	return 0;
}