Hacking is illegal, let me tell you, and if you are caught by a nasty webmaster you could be in trouble. Anyways, you can't really "hack" it so simply, since it is server based, not client-sided that stores your values and points, etc. So unless you're a professional hacker with hacking abilities it's going to be quite a hard go for you. Seriously, this is no easy job.
Again, don't cheat, compete fairly, win fairly, it gives more satisfaction