#include<stdio.h>
long n,m,a[16][16],smax;
void main()
{long i,j,k,s,t;
freopen("flip.in","r",stdin);
scanf("%lld %lld",&n,&m);
for(i=0;i<n;i++)
for(j=0;j<m;j++)
scanf("%lld",a[i]+j);
for(i=0;i<(l<<m);i++)
{s=0;
for(k=0;k<n;k++)
{for(t=j=0;j<m;j++)
if(i&(1<<j)) t+=-a[k][j]; 
else t+=a[k][j];
s+=t<-t ? -t : t;
}if(smax<s) smax=s;
}
freopen("flip.out","w",stdout);
printf("%lld\n",smax);
}