#include <bits/stdc++.h>

using namespace std;
ifstream f("flip.in");
ofstream g("flip.out");
int n, m, a[16][16], sum[16];
int maxim, s;

void Read()
{
  f>>n>>m;
  for(int i = 0;i < n;++i)
    for(int j = 0;j < m;++j)
      f>>a[i][j];
}

void Solve()
{
  for(int mask = 0;mask < 1 << n;++mask)
  {
    memset(sum, 0, sizeof(sum));
    for(int i = 0;i < n;++i)
      if(mask & (1 << i))
        for(int j = 0;j < m;++j)
          sum[j] -= a[i][j];
      else
        for(int j = 0;j < m;++j)
          sum[j] += a[i][j];
    s = 0;
    for(int i = 0;i < m;++i)
      s += abs(sum[i]);
    maxim = max(maxim, s);
  }
}

int main()
{
  Read();
  Solve();
  g<<maxim;
  return 0;
}