//#include <iostream>
#include <fstream>
#include <climits>
using namespace std;
ifstream f("flip.in");
ofstream g("flip.out");
int main()
{
    long long a[20][20],i,j,n,m, mmin = INT_MAX, s, imin;
    f >> n >> m;
    //cout <<n<<m;
    for(i=0; i<n; ++i){
        s=0;
        for(j=0; j<m; ++j){
            f >> a[i][j];
            s += a[i][j];
        }
        if(s<mmin){
            mmin = s;
            imin = i;
        }
    }
    for(i=0;i<m;i++){
        a[imin][i] *= -1;
    }
    mmin = INT_MAX;
    for(j=0; j<m; ++j){
        s=0;
        for(i=0; i<n; ++i){
            s += a[i][j];
        }
        if(s<mmin){
            mmin = s;
            imin = j;
        }
    }
    for(i=0;i<n;i++){
        a[i][imin] *= -1;
    }
    s=0;
    for(i=0; i<n; i++){
        for(j=0; j<m; j++){
            s += a[i][j];
            //out << s << " ";
        }
    }
    g << s;
    g.close();
    f.close();
    return 0;
}