#include<fstream>
using namespace std;
int max ( int a, int b)
{
    if(a>b)
    return a;
    else
    return b;}
int main()
{
    int n,i,j,S=0,m,a[30][30],s1[30],s2[30],Sum[30][30],maxim;
    ifstream f("flip.in", ios::in);
    ofstream g("flip.out", ios::out);
    f>>n;
    f>>m;
    for(i=1;i<=n;i++)
    for(j=1;j<=m;j++)
    f>>a[i][j];
    for(i=1;i<=n;i++)
    for(j=1;j<=m;j++)
    S=S+a[i][j];
    for(i=1;i<=n;i++)
    {s1[i]=0;
    for(j=1;j<=m;j++)
    s1[i]=s1[i]+a[i][j];}
    for(j=1;j<=m;j++)
    {s2[j]=0;
    for(i=1;i<=n;i++)
    s2[j]=s2[j]+a[i][j];}
    for(i=1;i<=n;i++)
    for(j=1;j<=m;j++)
    Sum[i][j]=max(max(S-2*s1[i],S-2*s2[j]),S-s1[i]-s2[j]);
    maxim=Sum[1][1];
    for(i=1;i<=n;i++)
    for(j=1;j<=m;j++)
    if(Sum[i][j]>maxim)
    maxim=Sum[i][j];
    g<<maxim;
    f.close();
    g.close();
    return 0;}