#include<cstdio>
int v[20][20];
int main()
{
    freopen("flip.in","r",stdin);
    freopen("flip.out","w",stdout);
    int n,m,i,j,k,s=0,sum=0,maxs=0;
    scanf("%d%d",&n,&m);
    for(i=1;i<=n;i++)
        for(j=1;j<=m;j++)
            scanf("%d",&v[i][j]);
    for(i=0;i<(1<<m);i++)
        {
        s=0;
        for(j=1;j<=n;j++)
            {
            sum=0;
            for(k=1;k<=m;k++)
                if (i&(1<<(k-1)))
                    sum+=v[j][k];
                else
                    sum-=v[j][k];
            if (sum<-sum)
                s=s-sum;
            else
                s=s+sum;
            }
        if (s>maxs)
            maxs=s;
        }
    printf("%d\n",maxs);
return 0;
}