Hi Codeforces,

As I've begun to compete more frequently, I've noticed that quite a few recent contests have ended in a large number of solutions being hacked, leading me to frequently jump hundreds of places.

Some examples: https://codeforces.com/contest/1182 (B), https://codeforces.com/contest/1187 (D). (I am not hating on these contests at all, just using them as examples. In fact, I very much enjoyed the problems in both contests.)

I've also heard of a lot of hacks in other contests that occur, such as CodeCraft, where people fail multiple problems from hacks.

So I'm wondering:

1.) Has anyone noticed a similar trend? Is it getting worse?

2.) Is there something that problem setters/testers can do to stop this, or at least minimize its occurrence?

3.) Also, what makes some contests virtually hack-free, while others have so many?

If anyone has any insight, please share it below.