#include <stdio.h>             
   int n,m,a[20][20],st[20],sol;             
     void verif()       
      {       
          int i,j,aux,tot;       
          for(tot=0,i=0;i<n;i++)       
            {       
         for(j=0,aux=0;j<m;j++)       
           aux+=st[j]*a[i][j];       
         tot+=((aux>0)?aux:-aux);       
           }       
        if(tot>sol) sol=tot;       
      }       
          
    void back(int i)       
      {       
         if(i<m)       
           {       
          st[i]=1;       
          back(i+1);       
         st[i]=-1;       
  back(i+1);       
  }       
  else verif();       
  }              
  int main ()       
  {       
  FILE *fi=fopen("flip.in","r"),       
  *fo=fopen("flip.out","w");       
  int i,j;       
  fscanf(fi,"%d %d",&n,&m);       
  sol=-1;       
  for(i=0;i<n;i++)       
  for(j=0;j<m;j++)       
  fscanf(fi,"%d",&a[i][j]);       
  back(0);       
  fprintf(fo,"%d",sol);       
  return(0);       
}