#include <iostream>
#include <fstream>
#define inf 1<<30
#define nmax 17
using namespace std;
int n,m,maxim=-inf;
int p[nmax];
int a[nmax][nmax];

void calc()
{
    int i,j,s,t=0;
    for (j=1;j<=m;j++) {
        s=0;
        for (i=1;i<=n;i++)
            s+=a[i][j]*p[i];

        if (s<0)
            s=-s;
        t+=s;
    }
    maxim=max(maxim,t);
}
void rez(int k)
{
    if (k>n)
        calc();
    else {
        p[k]=1;
        rez(k+1);
        p[k]=-1;
        rez(k+1);
    }
}
int main()
{
    ifstream f("flip.in");
    ofstream g("flip.out");
    int i,j;
    f>>n;
    f>>m;
    for (i=1;i<=n;i++)
        for (j=1;j<=m;j++)
            f>>a[i][j];
    rez(1);
    g<<maxim;
    return 0;
}