#include <iostream>
#include <fstream>
#include <cstring>

using namespace std;

string filename = "flip";

ifstream fin(filename + ".in");
ofstream fout(filename + ".out");

const int NMAX = 16;

int a[NMAX + 5][NMAX + 5];

int main()
{
    int n,m;
    fin>>n>>m;
    for(int i=1;i<=n;i++)
    {
        for(int j=1;j<=m;j++)
        {
            fin>>a[i][j];
        }
    }
    int rez=0;
    for(int mask = 0;mask < (1<<m);mask++)
    {
        int sum=0;
        for(int i=1;i<=n;i++)
        {
            int slin=0;
            for(int j=1;j<=m;j++)
            {
                if(mask&(1<<(j-1)))
                    slin+=-a[i][j];
                else
                    slin+=a[i][j];
            }
            sum+=abs(slin);
        }
        rez=max(rez,sum);
    }
    fout<<rez;
    return 0;
}