#include <iostream>
#include <fstream>
using namespace std;

ifstream fin("flip.in");
ofstream fout("flip.out");

int m, n, ma, slinie, s, v[20][20];
int rez[20];

void bkt(int k)
{
    if(k==n+1)
        {   s=0;
            slinie;
            for(int i=1;i<=m;i++)
            {
                slinie = 0;
                for(int j=1;j<=n;j++)
                {
                    if(rez[j]==1)
                        slinie+= (v[i][j]*(-1));
                    else
                        slinie+= v[i][j];

                }
                if(slinie < 0 ) slinie *=-1;
                s+=slinie;

            }
           ma=max(s, ma);
           //cout<<s<<endl;
        }
    else
        {   rez[k]=0;
            bkt(k+1);
            rez[k]=1;
            bkt(k+1);
        }
}


int main()
{
    fin>>n>>m;
    for ( int i = 1 ; i <= n ; i++ )
    {
        for ( int j = 1 ; j <= m ; j++ )
        {
            fin>>v[i][j];

        }

    }
    bkt(1) ;
  fout<<ma;
}