#include<cstdio>
#include<cstdlib>
#define M 20
long n,i,j,m,smax,s,k,t,a[M][M];
int main ()
{
	freopen("flip.in" , "r" , stdin);
	scanf("%ld %ld" , &n , &m );
	for(i=0;i<n;i++)
		for(j=0;j<m;j++)
			scanf("%ld" , &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("%ld\n" , smax);
	return 0;
}