#include <fstream>
#include <cmath>

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

int v[20][20], n, m, sol, vtemp[20], solmax, soltemp[20], i, j, k;

int main()
{
in>>n>>m;

for (i=0; i<n; ++i)
  for (j=0; j<m; ++j)
    in>>v[i][j], vtemp[i]+=v[i][j];

for (k=0; k< 1<<m; ++k)
  {
  sol=0;

  for (i=0; i<n; ++i)
    soltemp[i]=vtemp[i];

  for (j=0; j<m; ++j)
    if (1<<j & k)
      for (i=0; i<n; ++i)
        soltemp[i]-=v[i][m-j-1]*2;

  for (i=0; i<n; ++i)
    sol+=std::abs(soltemp[i] );

  solmax=std::max(solmax, sol);
  }

out<<solmax;
}