#include <iostream>
#include <fstream>
#include <cmath>
#define max(a,b) (a>b?a:b)
using namespace std;
ifstream f("flip.in");
ofstream g("flip.out");
int M,N,s,rs,i,j,mval,nval,conf[16][16],comut[16];
int summax(int x)
{
  if(x==M)
  {
      for(i=0;i<=N;i++)
        {rs=0;
            for(j=0;j<M;j++)
        rs=rs+conf[i][j]*comut[j];
      s=s+abs(rs);}
      g<<s;
  }
  else
  {
      comut[x]=1;
      mval=summax(x+1);
       comut[x]=-1;
      nval=summax(x+1);
      return max(nval,mval);

  }
}
int main()
{
   f>>M>>N;
   for(i=0;i<N;i++)
    for(j=0;j<M;j++)
    f>>conf[i][j];

   g<<summax(0);
    return 0;
}