#include <bits/stdc++.h>

using namespace std;
ifstream f("flip.in");
ofstream g("flip.out");
int n, m, a[17][17], c[17];
long long smax;
void backtracking(int step) {
  if (step > m) {
    long long sumf = 0;
    for (int i = 0; i < n; i++) {
      long long sum = 0;
      for (int j = 0; j < m; j++) {
        sum += c[j] * a[j][i];
      }
      if (sum < 0) {
        sumf += sum * (-1);
      } else {
        sumf += sum;
      }
    }
    smax = max(smax, sumf);
    return;
  }
  c[step] = 1;
  backtracking(step + 1);
  c[step] = -1;
  backtracking(step + 1);
}
int main() {
  f >> m >> n;
  for (int i = 0; i < m; i++) {
    for (int j = 0; j < n; j++) {
      f >> a[i][j];
    }
  }
  backtracking(0);
  g << smax;
  return 0;
}