#include <iostream>
#include <cstdio>
using namespace std;

int mat[20][20],n,m,col[20],maxn=0;

void citire()
{
    scanf("%d%d",&n,&m);
    for (int i=1; i<=n; ++i)
        for (int j=1; j<=m; ++j)
            scanf("%d",&mat[i][j]);
}

int main()
{
    freopen("flip.in","r",stdin);
    freopen("flip.out","w",stdout);
    citire();
    for (int i=1;i<=m;++i)
        for (int j=1;j<=n;++j)
            col[i]+=mat[j][i];
    for (int i=0 ; i<(1<<n) ; ++i)
    {
        int sum=0;
        for (int c=1;c<=m;++c)
            {
                int aux_sum=0;
                for (int l=1;l<=n;++l)
                    if (((1<<(l-1)) & i)!=0)
                        aux_sum+=(mat[l][c])*(-1);
                    else
                        aux_sum+=mat[l][c];
                if (aux_sum<0)
                    sum+=(aux_sum * (-1));
                else
                    sum+=aux_sum;
            }
        if (sum>maxn)
            maxn=sum;
    }
    printf("%d",maxn);
    return 0;
}