#include<fstream> 
#include<cmath> 
using namespace std; 
ifstream f("flip.in"); 
ofstream g("flip.out"); 
int i,j,n,m,smax,s,v1[20],v[20],a[20][20]; 
int main() 
{f>>n>>m; 
for(i=1;i<=n;++i) 
for(j=1;j<=m;++j) 
   
f>>a[i][j]; 
smax=0; 
while(1) 
{i=1; 
while(v[i]==1) 
  
v[i]=0,++i; 
if(i>n) 
    
break; 
v[i]=1; 
for(i=1;i<=m;++i) 
    
v1[i]=0; 
for(i=1;i<=m;++i) 
   
for(j=1;j<=n;++j) 
        
if(v[j]==1) 
            
v1[i]=v1[i]-a[j][i]; 
       
else
            
v1[i]=v1[i]+a[j][i]; 
s=0; 
for(i=1;i<=m;++i) 
    
if(v1[i]>0) 
        
s=s+v1[i]; 
    
else
        
s=s-v1[i]; 
if(smax<s) 
    
smax=s; 
} 
g<<smax<<'\n'; 
return 0; 
}