#include<fstream>
#define FOR for(i=1;i<=n;i++) for(j=1;j<=m;j++)
using namespace std;
ifstream f("flip.in");
ofstream g("flip.out");
int n,m,aux,i,j,s,max1=0,s1,k;
int a[100][100];
int b[100];
int main()
{
	f>>n>>m;
	FOR
		f>>a[i][j];
	for(i=1;i<(1<<m);++i)
	{
		aux=i; 
		s=0;
		for(j=1;j<=m;++j)
		{
			b[j]=aux&1;
			aux>>=1;                               
		}    
		for(k=1;k<=n;++k)
		{
			s1=0;
			for(j=1;j<=m;++j)
				(b[j])?(s1+=a[k][j]):(s1-=a[k][j]);                                                         
			if(s1<0)
				s-=s1;
			else 
				s+=s1;                       
		}
		if(s>max1)
			max1=s;
	}
	g<<max1;
	return 0;
}