#include<stdio.h> 
#include<iostream.h> 
int n,m,flip[16]; 
long matrice[16][16] ; 
long long sumamax=0,suma,b; 
void flipit() 
{     
suma=0;     
int i,j;     
for(i=0;i<n;i++)     
{         
b=0;             
for(j=0;j<m;j++)                 
b+=matrice[i][j]*flip[j];         
if(b<0)             
suma+= -1*b;                     
else             
suma+=b;     
}     
if(sumamax<suma)         
sumamax=suma; } 
void back(int cont) 
{     
if(cont==m)          
{         
flipit();         
return;    
}     
flip[cont]=1; back(cont+1);     
flip[cont]=-1; back(cont+1); } main() 
{     
int i,j;     
freopen("flip.in","r",stdin);     
freopen("flip.out","w",stdout);     
cin>>n>>m;     
for(i=0;i<n;i++)         
for(j=0;j<m;j++)             
cin>>matrice[i][j];     
back(0);     
cout<<sumamax<<"\n"; 
}