#include "fstream"

using namespace std;
int n,m;
int **p;
int *v;

int sum();
int main(){

    ifstream in;
    in.open("flip.in");

    in>>n>>m;

    p=new int*[n];

    for(int i=0;i<n;i++){ //citire
        p[i]=new int[m];
        for(int j=0;j<m;j++){
            in>>p[i][j];
        }
    }

    in.close();

    int max=0;

    v=new int[m];
    v[0]=-1;

    int k=1;
    while(k>=0){



        v[k]=-1;

        if(k==m){
            if(max<sum()){
                max=sum();
            }
            k--;
            while(v[k]==1){
                    k--;
            }

            if(k>=0){
                v[k]*=-1;
                k++;
            }
        }else{
            k++;
        }
    }

    ofstream off;
    off.open("flip.out");
    off<<max;

    off.close();

    return 0;
}

int sum(){
    int sum=0;
    for(int i=0;i<n;i++){
        int aux=0;
        for(int j=0;j<m;j++){
            aux+=p[i][j]*v[j];
        }
        if(aux<0){
            aux*=-1;
        }
        sum+=aux;
    }
    return sum;
}