#include <vector>
#include <fstream>
#include <iostream>
using namespace std;
typedef vector<vector<int> > MATRIX;
typedef unsigned int uint;
int maxi;
MATRIX table;



void back_flip(vector<int> possible_solution) {
	if(possible_solution.size() == table.size()) {
		int sum1 = 0, sum2 = 0;
		for(uint i = 0; i < table.size(); i++) 
			for(uint j = 0; j < table[i].size(); j++) {
				sum1 += table[i][j] * possible_solution[i];
				sum2 += table[i][j] * possible_solution[j];
			}
		if(sum1 > maxi)
			maxi = sum1;
		if(sum2 > maxi)
			maxi = sum2;		
	}	
	else {
		possible_solution.push_back(1);
		back_flip(possible_solution);
		possible_solution.pop_back();
		possible_solution.push_back(-1);
		back_flip(possible_solution);
	}
}

int main() {
	fstream input("flip.in", ios_base::in);
	fstream output("flip.out", ios_base::out);
	int n,m;
	input >> n >> m;
	table = vector<vector<int> >(n, vector<int>(m, 0));
	for(int i = 0; i < n; i++) 
		for(int j = 0; j < m; j++) 
			input >> table[i][j];
	maxi = INT_MIN;
	vector<int> solution;
	back_flip(solution);
	output << maxi;
	input.close();
	output.close();
	return 0;
}