#include<stdio.h>
#include<stdlib.h>
#include<math.h>
FILE *f=fopen("flip.in","r"),*g=fopen("flip.out","w");
int n,m,a[17][17],semn[17];
long long s1,s2,smax;
void citire()
{
fscanf(f,"%d%d",&n,&m);
for(int j,i=0;i<n;i++)
	{for(j=0;j<m;j++)
		{fscanf(f,"%d",&a[i][j]);
		}
	}
}
inline void sum()
{int j,i;
s1=0;
for(j=0;j<m;j++)
	{s2=0;
	for(i=0;i<n;i++)
		{s2=s2+semn[i]*a[i][j];
		}
	s1+=abs(s2);
	}
if(smax<s1)
	{smax=s1;
	}
}
void back(int k)
{
if(k==n)
	{sum();
	}
else
	{semn[k]=1;
	back(k+1);
	semn[k]=-1;
	back(k+1);
	}
}
int main()
{
citire();
back(0);
fprintf(g,"%d",smax);
fclose(f);
fclose(g);
return 0;	
}