Here are some submissions of F 279625545 279590206 279609951 279581737
All of them have some ANTIHACK
macros or something like that. Obviously they can't anti-hack, they just make their codes hackable. But the problem comes: many submissions have slightly difference to others so they can't be easily hacked just by one code. Almost every hackable code needs special designs, which is quite annoying :(
And I also found some lol submissions: 279596731 279629539. They have the cheating codes in the submission, but the submission is surprisingly unhackable lol
Just by checking the codes after sorting by execution time, I found that more than 4 in 5 submissions are hackable, omg...