#include <iostream>
#include <fstream>
using namespace std;
int a[20][20], m, n, o, p, i, q, ok, k, maxi, j;
int main()
{
    ifstream fin("flip.in");
    ofstream fout("flip.out");
    fin>>n>>m;
    for(i=1; i<=n; i++)
        for(q=1; q<=m; q++) {fin>>a[i][q]; maxi+=a[i][q];}
    for(i=1; i<=1<<n; i++)
    {
        ok=0;
        for(q=1; q<=m; q++)
        {
            o=0;
            p=0;
            for(j=0; j<n; j++)
            {
                if(i&1<<j) o+=a[j+1][q];
                else p+=a[j+1][q];
            }
            if(o-p>p-o) ok+=o-p;
            else ok+=p-o;
        }
        if(maxi<ok) maxi=ok;
    }
    fout<<maxi;
    return 0;
}