#include<fstream>
using namespace std;

int n, m, i, j;
int a[1000][1000], maxim=0, s[20];

int cont()
{
    int sum, summ=0,i, j;
    for(j=1;j<=m;j++)
    {
        sum=0;
        for(i=1;i<=n;i++)
            sum+=s[i]*a[i][j];
        if(sum<0) sum=-sum;
        summ+=sum;
    }
     if(summ>maxim) maxim=summ;
}
int backtraking(int k)
{
    if(k<=n)
    {
        s[k]=1;
        backtraking(k+1);
        s[k]=-1;
        backtraking(k+1);
    }
    else
        cont();
}

int main()
{
    ifstream fin("flip.in");
    fin>>n>>m;
    for(i-1;i<=n;i++)
    {
        for(j=1;j<=m;j++)
        {
            fin>>a[i][j];
        }
    }
    fin.close();
    backtraking(1);
    ofstream fout("flip.out");
    fout<<maxim;
    fout.close();
}