#include <iostream>
#include <stdio.h>

using namespace std;

int x,n,m,v[17][17],s,p,sr[17],maxp,k,sumc,semn,ran,i,j;
int abss(int a)
{
	if (a>0) return a;
	else return -a;
}

int main()
{
	maxp=-1234567890;
	FILE *f;
	f=fopen("flip.in","r");
	fscanf(f,"%i %i",&n,&m);
	p=1;
	for(i=1;i<=n;i++)
	{
		p*=2;
		for(int j=1;j<=m;j++)
		{
			fscanf(f,"%i",&v[i][j]);					
		}
	}
	
	for(i=0;i<p;i++)
	{
		k=i;
		sumc=0;
		for(j=1;j<=n;j++) sr[j]=0;
		for(j=1;j<=m;j++)
		{
			
			if (k%2==1)	semn=-1;
			else semn=1;
			k=k>>1;
			for(ran=1;ran<=n;ran++)
			{
				sr[ran]+=semn*(v[ran][j]);
			}
		}
		for(j=1;j<=n;j++) sumc+=abss(sr[j]);
		if (sumc>maxp) maxp=sumc;
	}
	fclose(f);
	f=fopen("flip.out","w");	
	
	
	fprintf(f,"%i",maxp);
	return 0;
}