#include <vector>
#include <iostream>
#include <fstream>

using namespace std;

vector<vector<int>> arr;
vector<int> mul;
int r, c;
int ans = -2000000000;

void flip_coloane() {
    vector<int> col_sum(c, 0);
    for (int j = 0; j < c; j++) {
        for (int i = 0; i < r; i++)
            col_sum[j] += arr[i][j] * mul[i];
    }
    int temp_sum = 0;
    for (int j = 0; j < c; j++) {
        temp_sum += abs(col_sum[j]);
    }
    ans = max(temp_sum, ans);
}

void flip_linii(int i) {
    if (i == r)
        flip_coloane();
    else {
        mul[i] = 1;
        flip_linii(i+1);
        mul[i] = -1;
        flip_linii(i+1);
    }
}

int main() {
    ifstream fin("flip.in");
    ofstream fout("flip.out");

    fin >> r >> c;

    arr = vector<vector<int>>(r, vector<int>(c));
    mul.resize(r);

    for (int i = 0; i < r; i++) {
        for (int j = 0; j < c; j++) {
            fin >> arr[i][j];
        }
    }

    flip_linii(0);

    fout << ans;
}