#include <fstream>
#include <cmath>
using namespace std;

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

int n, m;

int v[17][17];

int calcSum(int NrPerm) {
  int Sum = 0;
  for(int i = 1; i <= n; i++) {
    int SumLin = 0;
    for(int j = 1; j <= m; j++)
      if(NrPerm & (1 << (j - 1)))
        SumLin += v[i][j];
      else
        SumLin -= v[i][j];
    Sum += abs(SumLin);
  }
  return Sum;
}

int main() {
  cin >> n >> m;
  for(int i = 1; i <= n; i++)
    for(int j = 1; j <= m; j++)
      cin >> v[i][j];
  int sol = 0;
  for(int i = 0; i < (1 << m); i++)
    sol = max(sol, calcSum(i));
  cout << sol;
  return 0;
}