#include<bits/stdc++.h>

using namespace std;

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

#define NMAX 20

int ma[NMAX][NMAX];
int n,m;
int sol[NMAX];
int maxim = 0;

void calc()
{
    int sum = 0;
    for(int j=1;j<=m;j++)
    {
        int sum_col = 0;
        for(int i=1;i<=n;i++)
        {
            sum_col += ma[i][j] * sol[i];
        }
        sum+= abs(sum_col);
    }
    if(sum > maxim)
        maxim = sum;
}

void bkt(int k)
{
    if(k == n+1)
    {
        calc();
    }
    else
    {
        sol[k] = 1;
        bkt(k+1);

        sol[k] = -1;
        bkt(k+1);
    }

}


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

    bkt(1);
    fout<<maxim;

}