#include <cstdio>

using namespace std;

int main()
{
    freopen("flip.in", "r", stdin);
    freopen("flip.out", "w", stdout);

    int n, m, mat[18][18];
    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 sum, s, total=0;
    bool v[18]={0};
    while(!v[0])
    {
        int i=m;
        while(v[i] == 1)
        {
            v[i]=0;
            i--;
        }
        v[i]=1;
        sum=0;

        for(i=1; i<=n; i++)
        {
            s=0;
            for(int j=1; j<=m; j++)
                if(v[j]) s+=mat[i][j];
                else s-=mat[i][j];
            if(s < 0) s=-s;
            sum+=s;
        }
        if(total < sum) total=sum;
    }
    printf("%d", total);
}