#include <iostream>
#include <fstream>

using namespace std;

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

    int n,m,suma = 0,suma2 = 0,suma3 = 0;

    fin>>n>>m;

    int V[n][m];

    for(int i = 0;i < n;i++){
        for(int j = 0;j < m;j++){
            fin>>V[i][j];
        }
    }
    for(int i = 0;i < n;i++){
        for(int j =0;j < m;j++){
            suma += V[i][j];
        }
    }
    suma2 = suma;
    suma3 = suma;
    for(int i = 0;i < n;i++){
        for(int j = 0;j < m;j++){
            for(int k = 0;k < n;k++){
                if(V[k][j] < 0){
                    suma2 = suma2 - (V[k][j] * 2);
                }
                else{
                    suma2 = suma2 - (V[k][j] * 2);
                }
            }
            for(int k = 0;k < m;k++){
                if(V[i][k] < 0){
                    suma2 = suma2 - (V[i][k] * 2);
                }
                else{
                    suma2 = suma2 - (V[i][k] * 2);
                }
            }
            if(suma3 < suma2){
                suma3 = suma2;
            }
            else{
                suma2 = suma;
            }
        }
    }
    fout<<suma3;
}