#include <stdio.h>

FILE *f,*s;

long int n,m,i,j,s1,s2,v[50],t[50][50],max;

void generare(int k)
{
	if(k>n)
	{
		s1=0;
		for(i=1;i<=m;i++)
		{
			s2=0;
			for(j=1;j<=n;j++)
				s2+=t[j][i]*v[j];

			if(s2<0)
				s2*=-1;

			s1+=s2;
		}

		if(s1>max)
			max=s1;
	}
	else
	{
		v[k]=1;  generare(k+1);
		v[k]=-1; generare(k+1);
	}
}

int main()
{
	f=fopen("flip.in","r");
	s=fopen("flip.out","w");

	fscanf(f,"%ld %ld\n",&n,&m);

	for(i=1;i<=n;i++)
	{
		for(j=1;j<=m;j++)
			fscanf(f,"%ld ",&t[i][j]);
		fscanf(f,"\n");
	}

	max=-2000000;

	generare(1);

	fprintf(s,"%ld",max);

	return 0;
}