#include <bits/stdc++.h>
using namespace std;

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

int v[20];
int mat[20][20];
int n,m,maxs;

void backtr(int k){
    if(k == m+1){
        int i,j,s =0,sf = 0;
        for(i = 1; i <= n; i++){
            s = 0;
            for(j = 1; j <= m; j++){
                s += mat[i][j]*v[j];
            }
            if(s < 0){
                s = -s;
            }
            sf += s;
        }
        maxs = max(maxs,sf);
    }else{
        v[k] = 1;
        backtr(k+1);
        v[k] = -1;
        backtr(k+1);
    }
}

int main()
{
    int i,j;
    fin>>n>>m;
    for(i = 1; i <= n; i++){
        for(j = 1; j <= m; j++){
            fin>>mat[i][j];
        }
    }
    backtr(1);
    fout<<maxs<<'\n';
    return 0;
}