#include <fstream>

using namespace std;

ifstream cin("flip.in");
ofstream cout("flip.out");

int n, m, a[20][20], vizx[20], lin[20], col[20], tot;
int main()
{
    cin >> n >> m;

    for(int i = 0; i < n; i++)
        for(int j = 0; j < m; j++)
        {
            cin >> a[i][j];
            lin[i] += a[i][j];
            col[j] += a[i][j];
            tot += a[i][j];
        }

    int nmax = (1 << n) - 1;
    int mmax = (1 << m) - 1;

    int smax = tot;
    for(int i = 0; i <= nmax; i++)
        for(int j = 0; j <= mmax; j++)
        {
            int k = 0;
            int s = tot;

            for(int x = 0; x < n; x++)
                if((1 << x) & i)
                {
                    s -= 2 * lin[x];
                    vizx[++k] = x;
                }

            for(int y = 0; y < m; y++)
                if((1 << y) & j)
                {
                    s -= 2 * col[y];
                    for(int q = 1; q <= k; q++)
                        s += 4 * a[vizx[q]][y];
                }

            if(s > smax)
                smax = s;
        }

    cout << smax;

    return 0;
}