#include <stdio.h>
int n,m;
long a[500][16];
void citire()
{int i,j; FILE *f;
 f=fopen("flip.in","r");
 fscanf(f,"%d %d",&n,&m);
 for(i=0;i<n;i++)
   for(j=0;j<m;j++)
     fscanf(f,"%ld",&a[i][j]);
 fclose(f);
}
long fl(int p)
{long s1=0;
 for(int q=0;q<m;q++)
   s1+=-a[p][q];
 return s1;
}
long fc(int p)
{long s1=0;
 for(int q=0;q<m;q++)
   s1+=-a[q][p];
 return s1;
}
void flip()
{int i,j,x; long k=0,s; FILE *f;
 for(i=0;i<n;i++)
   {s=0;
    for(j=0;j<m;j++)
     s+=a[i][j];
    if(s<=fl(i)) for(x=0;x<m;x++)
		    a[i][x]=-a[i][x];
   }
 for(i=0;i<n;i++)
   {s=0;
    for(j=0;j<m;j++)
     s+=a[j][i];
    if(s<=fc(i)) for(x=0;x<n;x++)
		    a[x][i]=-a[x][i];
   }
for(i=0;i<n;i++)
  for(j=0;j<m;j++)
    k+=a[i][j];
 f=fopen("flip.out","w");
 fprintf(f,"%ld",k);
 fclose(f);
}
void main()
{citire();
 flip();
}