#include <fstream>

using namespace std;
ifstream in("flip.in");
ofstream out("flip.out");

int main()
{
    int n,i,m,v[20][20];
    long long min_linii=999999999999,min_coloane=999999999999,linii=0,coloane=0,j,sum=0,indice_linii,indice_coloane;
    in>>n>>m;
    for(i=1; i<=n; i++)
    {
        linii=0;
        for(j=1; j<=m; j++)
        {
        in>>v[i][j];
            linii+=v[i][j];

        }
        if(linii<min_linii)
        {
            min_linii=linii;
            indice_linii=i;
        }

    }
    for(j=1; j<=m; j++)
    {
        coloane=0;
        for(i=1; i<=n; i++)
        {
            coloane+=v[i][j];
        }
        if(coloane<min_coloane)
        {
            min_coloane=coloane;
            indice_coloane=j;
        }
    }
    for(i=1; i<=n; i++)
    {
        v[i][indice_coloane]*=(-1);
    }
    for(i=1; i<=m; i++)
    {
        v[indice_linii][i]*=(-1);
    }
    sum=0;
    for(i=1; i<=n; i++)
        for(j=1; j<=m; j++)
            sum+=v[i][j];
    out<<sum;
    return 0;
}