#include <iostream>
#include <cmath>
#include <fstream>
using namespace std;
int v[20][20],i,j;

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



int main(){

    int n,m,sumabarosana=0;
    in >>n>>m;
    int x[n+m+1]={0};

    x[n+m]=1;
    for ( i=1;i<=n;i++)
        for ( j=1;j<=m;j++){
          in >>v[i][j];
          sumabarosana+=v[i][j];}
    int s;
    while (x[0]==0){
        s=0;
        for ( i=1;i<=n;i++){
                int s1=0;
            for ( j=1;j<=m;j++){
                    if (x[j]==0)
                        s1+=v[i][j];
                    else s1-=v[i][j];
                }
          s+=abs(s1);

        }
        sumabarosana=max(s,sumabarosana);

            for(i=m;x[i]==1;i--)
        {
            x[i]=0;
        }
        x[i]++;

    }
    out <<sumabarosana;
}