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

/*#define INPUT "text.in"
#define OUTPUT "text.out"
ifstream fin(INPUT);
ofstream fout(OUTPUT);*/

ifstream fin("flip.in");
ofstream fout("flip.out");
 int n,m;
 int a[17][17], schimb[17];
 int sumMax;

void calc()
{
    int sumCurrenta=0;
    int sum;

    for(int j=1;j<=m;j++)
    {
        sum=0;
        for(int i=1;i<=n;i++)
            if(schimb[i]) sum+=(-a[i][j]);
            else sum+=a[i][j];
     if(sum<0)sumCurrenta+=(-sum);
      else sumCurrenta+=sum;
    }
    if(sumMax<sumCurrenta) sumMax=sumCurrenta;
}
void gen(int k)
{
    if(k>n) calc();
    else for(int i=0;i<=1;i++)
    {
        schimb[k]=i;
        gen(k+1);
    }

}
void citire()
{
    fin>>n>>m;
   for(int i=1;i<=n;i++)
    for(int j=1;j<=m;j++) fin>>a[i][j];
}
int main()
{
    citire();
    gen(1);
    fout<<sumMax;
}