#include <fstream>

using namespace std;

int main(){

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

    int N, M;
    fin >> N >> M;
    int A[N][M];

    for(int i = 0; i < N; ++i){
        for(int j = 0; j < M; ++j){
            fin >> A[i][j];
        }
    }
    int sum, sum_inv, total_sum = 0;
    for(int i = 0; i < N; ++i){
        sum = 0;
        sum_inv = 0;
        for(int j = 0; j < M; ++j){
            sum += A[i][j];
            sum_inv -= A[i][j];
        }
        if(sum_inv > sum){
            for(int j = 0; j < M; ++j){
                A[i][j] = -A[i][j];
            }
        }
    }

    for(int i = 0; i < M; ++i){
        sum = 0;
        sum_inv = 0;
        for(int j = 0; j < N; ++j){
            sum += A[j][i];
            sum_inv -= A[j][i];
        }
        if(sum_inv > sum){
            for(int j = 0; j < N; ++j){
                A[j][i] = -A[j][i];
            }
        }
        total_sum += max(sum_inv, sum);
    }

    fout << total_sum << "\n";

    return 0;
}