#include<cstdio>
int a[20][20],b[20];
int main()
{
freopen("flip.in","r",stdin);
freopen("flip.out","w",stdout);
int n,m,aux,i,j,s,max1=0,s1,k;
scanf("%d %d\n",&n,&m);
for(i=1;i<=n;++i)
	for(j=1;j<=m;++j)
		scanf("%d ",&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;
	}
printf("%d",max1);
return 0;
}