#include<stdio.h>
int semn[16],a[16][16],n,m,i,j,sum;
void suma()
{int s[16]={0},t=0;
for(i=0;i<m;i++) for(j=0;j<n;j++) s[i]+=a[j][i]*semn[j];
for(i=0;i<m;i++) if(s[i]>0) t+=s[i];
                       else t+=(-1)*s[i];
if(t>sum) sum=t;
}
void back(int x)
{if(x==n) suma();
     else {semn[x]=-1;back(x+1);
           semn[x]=1;back(x+1);
	      }
}
int main()
{freopen("flip.in","r",stdin);
freopen("flip.out","w",stdout);
scanf("%d%d",&n,&m);
for(i=0;i<n;i++) for(j=0;j<m;j++) scanf("%d",&a[i][j]);
back(0);
printf("%d",sum);
return 0;
}