#include<stdio.h>

int a[16][16],n,m,s[16],aux;
long smax,sum;

void bk(int);

int main()
{
	int i,j;

	freopen("flip.in","r",stdin);
	freopen("flip.out","w",stdout);

	scanf("%d %d",&n,&m);

	for(i=1;i<=n;i++)
		for(j=1;j<=m;j++)
			scanf("%d",&a[i][j]);

	smax=-2000000000;

	for(aux=0;aux<(1<<n);aux++)
	{
		for(i=1;i<=n;i++)
		{
			if((aux>>(i-1))&1)
				for(j=1;j<=m;j++)
					s[j]-=a[i][j];
			else
				for(j=1;j<=m;j++)
					s[j]+=a[i][j];
		}

		sum=0;

		for(j=1;j<=m;s[j++]=0)
		{
			if(s[j]<0)
				sum-=s[j];
			else
				sum+=s[j];

		}

		if(sum>smax)
			smax=sum;
	}
	printf("%d",smax);

	return 0;
}