#include <fstream>

using namespace std;

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

int n, m, i, j, sol;
int x[20]; /// semn
int a[20][20];

inline int solve (){
    int i, j, s, sum;
    s = 0;
    sum = 0;
    for (i=1; i<=n; i++){
        s = 0;
        for (j=1; j<=m; j++){
            s += a[i][j]*x[j];
        }
        sum += ((s >= 0) ? s : s*(-1));
    }
    return sum;
}

inline void bkt (int k){
    int sum, s, i, j;
    if (k == m + 1){
        sum = solve ();
        sol = max (sol, sum);
        return ;
    }
    else{
        x[k] = -1;
        bkt (k + 1);
        x[k] = 1;
        bkt (k + 1);
    }
}

int main(){
    fin >> n >> m;
    for (i=1; i<=n; i++){
        for (j=1; j<=m; j++){
            fin >> a[i][j];
        }
    }
    bkt (1);
    fout << sol;
    return 0;
}