#include <fstream>
#include <iostream>
using namespace std;

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

int n, m, a[17][17], s1, s2, minim1 = 0x3f3f3f3f, minim2 = 0x3f3f3f3f, pmin1, pmin2, s;

int main ()
{
    fin >> n >> m;
    for (int i = 1; i <= n; i++)
        for (int j = 1; j <= m; j++)
            fin >> a[i][j];
    for (int i = 1; i <= n; i++)
    {
        s1 = 0;
        for (int j = 1; j <= m; j++)
        {
            s1 += a[i][j];
        }
        if (s1 < minim1)
            minim1 = s1, pmin1 = i;
    }
    for (int j = 1; j <= m; j ++)
        a[pmin1][j] *= (-1);
    for (int j = 1; j <= m; j++)
    {
        s2 = 0;
        for (int i = 1; i <= n; i++)
        {
            s2 += a[i][j];
        }
        if (s2 < minim2)
            minim2 = s2, pmin2 = j;
    }
    for (int i = 1; i <= n; i ++)
        a[i][pmin2] *= (-1);
    for (int i = 1; i <= n ;i ++)
        for (int j = 1; j <= m; j++)
        {
            s += a[i][j];
        }
    fout << s;
    return 0;
}