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