#include<cstdio>
using namespace std;
int main()
{
	freopen("flip.in","r",stdin);freopen("flip.out","w",stdout);
	int bin=0,lim,m,n,i,j,a[17][17],s=0,t=0,maxx=-2e9;
	scanf("%d%d",&n,&m);
	for(i=1;i<=n;++i)
		for(j=1;j<=m;++j)
			scanf("%d",&a[i][j]);
	if(n<=m)
		for(lim=1<<(n-1);bin<lim;++bin,t=0)
		{
			for(j=0;j<m;++j)
			{
				for(i=0;i<n;++i)
					if((bin>>i)&1)
						s-=a[i+1][j+1];
					else
						s+=a[i+1][j+1];
				s=s<0?-s:s;
				t+=s;s=0;
			}
			t=t<0?-t:t;
			if(maxx<t)
				maxx=t;
		}
	else
		for(lim=1<<(m-1);bin<lim;++bin,t=0)
		{
			for(i=0;i<n;++i)
			{
				for(j=0;j<m;++j)
					if((bin>>j)&1)
						s-=a[i+1][j+1];
					else
						s+=a[i+1][j+1];
				s=s<0?-s:s;
				t+=s;s=0;
			}
			t=t<0?-t:t;
			if(maxx<t)
				maxx=t;
		}
	printf("%d",maxx);
}