#include <iostream>
#include <cstdio>
#include <algorithm>
#include <time.h>
#include <cmath>
using namespace std;
#define nl '\n'
template<class a>
void print(a v) {
    //for_each(all(v), [](auto x) { cout << x; });
}
#define N 16
#define M 16
int n,m,tabla[N][M];
int SumaMax;
inline int sumaCurentaMax(int coloana){
    int suma = 0;
    for(int i=0;i<n;++i){
        int sumaPeLinie = 0;
        for(int j=0;j<m;++j){
            if((1<<j)&coloana){ // flip = true
                sumaPeLinie += -tabla[i][j];
            } else { // flip = false
                sumaPeLinie += tabla[i][j];
            }
        }
        suma += max(-sumaPeLinie,sumaPeLinie); // aici este flip pe linie sau nu
    }
    return suma;
}
int main() {
    ios_base::sync_with_stdio(false);
    freopen("flip.in","r",stdin);
    freopen("flip.out","w",stdout);
    clock_t tStart = clock();
    cin >> n >> m;
    for(int i=0;i<n;++i)
        for(int j=0;j<m;++j)
            cin >> tabla[i][j];

    for(int col=0;col<(1<<m);++col){
        SumaMax = max(sumaCurentaMax(col),SumaMax);
    }
    cout << SumaMax << nl;
    //printf("\nTime taken: %.2fs\n", (double) (clock() - tStart) / CLOCKS_PER_SEC);
}