#include<fstream>

using namespace std;

ifstream cin("filp.in");
ofstream cout("flip.out");
int n,m,a[20][20],sum,ma,sol,f[20];

void backtrack(){

for(int i=1;i<=(1 << n) - 1;i++){
 for (int j = 1; j <= n; ++j)
    f[j] = 1;
    sol=0;
 for(int j=i,bit=1;j>0;j/=2,++bit)  {
 if(j & 1)
 {
     f[bit]=-1;
 }
 else
    f[bit]=1;
 }
for(int l=1;l<=m;l++){
        sum=0;
for(int j=1;j<=n;j++)
sum+=a[j][l]*f[j];
sol+=sum > 0 ? sum : - sum;
}
ma = max(ma,sol);
}
    cout<<ma;
}
int main()  {
    cin>>n>>m;
    for(int i=1;i<=n;i++)
        for(int j=1;j<=m;j++)
        cin>>a[i][j];
    backtrack();
    return 0;
}