Guarding the farm

Can someone take a look at my code and say what I'm doing wrong ?
http://www.z-trening.com/submit.php?submit=7100083909&subm_code=1
Thanks in advance :)

In your function hilltop, you return 0 first time you encounter a higher adjacent field. You shouldn't do that, because you already marked this field, and when you end up on the same hill with this height ( because you didn't mark the whole hill ) you won't see that there is higher field (because the field that is the neighbour to the higher field is already marked).

Thanks a lot :) working now :D