#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); 
}