#include <bits/stdc++.h>
using namespace std;
ifstream in("flip.in");
ofstream out("flip.out");
int a[18][18],s,s1,ma;
short n,m,i,j,v[18];
void b(short k)
{
    if(k<=n)
    {
        v[k]=1;
        b(k+1);
        v[k]=-1;
        b(k+1);
    }
    else
    {
        for(j=1,s1=0; j<=m; ++j)
        {
            for(i=1,s=0; i<=n; ++i)
                s+=v[i]*a[i][j];
            if(s<0)
                s*=-1;
            s1+=s;
        }
        ma=max(ma,s1);
    }
}
int main()
{
    in>>n>>m;
    for(i=1; i<=n; ++i)
        for(j=1; j<=m; ++j)
            in>>a[i][j];
    b(1);
    out<<ma;
}