#include <cstdio>

using namespace std;
int n,m;
int a[20][20];
int col[20],line[20];
int b[20][20];
int s,contor;
int sir[450];
void citire()
{
    freopen("flip.in","r",stdin);
    scanf("%d %d", &n,&m);
    for(int i=1;i<=n;i++)
    {
        for(int j=1;j<=m;j++)
        {
            scanf("%d",&a[i][j]);
            col[j]+=a[i][j];
            line[i]+=a[i][j];
        }
    }
}
int minimal(int x[], int p)
{
    int minimum=1000001;
    int f=-1;
    for(int k=1;k<=p;++k)
    {
        if(minimum>x[k])
        {
            minimum=x[k];
            f=k;
        }
    }
    return f;
}
void comutare()
{
    //int l1=minimal(line,n),c2 = minimal(col,m);
    int l1,c2;
    for(int v=1;v<=n;v++)
    {
        l1=v;
        for(int x=1;x<=m;++x)
        {
            c2=x;
            int s=0;
            for(int i=1;i<=n;i++)
            {
                for(int j=1;j<=m;++j)
                {
                    if( i == l1 || j == c2)
                    {
                        b[i][j]=a[i][j]*(-1);
                        s+=b[i][j];
                    }
                    else
                    {
                        b[i][j]=a[i][j];
                        s+=b[i][j];
                    }
                }
            }
            sir[contor++]=s;
        }
    }
}
void afisare()
{
    for(int i=1;i<=n;i++)
    {
        for(int j=1;j<=m;j++)
        {
            printf("%3d",b[i][j]);
        }
        printf("\n");
    }
}
int main()
{
    freopen("flip.out","w",stdout);
    citire();
    comutare();
    //afisare();
    int maxim=-1;
    for(int i=1;i<=contor;++i)
        if(maxim < sir[i])
            maxim=sir[i];
    printf("%d\n",maxim);
    return 0;
}