#include<stdio.h>

long n,m,a[1001][1001],smax;
long i,j,k,s,t;

int main()
{

	freopen("flip.in","r",stdin);
	freopen("flip.out","w",stdout);

	scanf("%lld %lld",&n ,&m);

	for(i=0;i<n;i++)

		for(j=0;j<m;j++)

			scanf("%lld", 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;
	}
	printf("%lld",smax);

	return 0;
}