#include <fstream>

using namespace std;

int Max=-1000001,N,M,Arr[18][18],putereDe2;

fstream f("flip.in",ios::in);
ofstream g("flip.out");

void read();
void solve();

int main()
{
    read();
    solve();
    g<<Max;

    return 0;
}

void solve()
{
    int i,j,k,sum=0,temp;
    for(k=1;k<putereDe2;++k)
        {
            sum=0;
        for(i=1;i<=N;++i)
        {
             temp=0;
        for(j=1;j<=M;++j)
        {
            if(k&(1<<(j-1)))
                temp+=Arr[i][j];
            else
                temp-=Arr[i][j];
        }
        if(temp<0)temp*=(-1);
        sum+=temp;
        temp=0;
        }
   if(sum>Max)Max=sum;
        }
}

void read()
{
    int i,j;
    f>>N>>M;
    for(i=1;i<=N;++i)
        for(j=1;j<=M;++j)
            f>>Arr[i][j];
    putereDe2=1<<M;
}