#include <fstream>
#include <algorithm>
using namespace std;
//====================*
ifstream fin("flip.in");
ofstream fout("flip.out");
//====================*
int n, m, i, j, ok, k, minim, maxim, nr;
int v[1000001], w[1000001], o, s, stotal;
int a[1001][1001], ii, jj, i1, i2, j2;
int d[3][1000001], e[3][1000001], x;
//====================*
int main(){
     fin >> n >> m;
     for(i = 1; i <= n; i ++)
          for(j = 1; j <= m; j ++)
               fin >> a[i][j];
     while(v[m + 1]==0){
          x = 1;
          while(v[x] == 1){
               v[x] = 0;
               x ++;
          }
          v[x] = 1;
          stotal = 0;
          for(i = 1; i <= n; i ++){
               s = 0;
               for(j = 1; j <= m; j ++){
                    if(v[j] == 1)
                         s += a[i][j];
                    else
                         s -= a[i][j];
               }
               if(s < 0)
                    s *= (-1);
               stotal = stotal + s;
          }
          if(maxim < stotal)
               maxim = stotal;
     }
     fout << maxim;
     return 0;
}