Why?↵
↵
**Weak pretests discourage guessing.**↵
↵
There are many contestants who only have a faint idea of why their solution↵
works at all. The problem style of recent years has contributed to this.↵
If the solution boils down to "check this elegant condition, answer↵
`YES` or `NO` based on that", then it is very much possible to solve ↵
problems by guessing. Especially with full feedback.↵
↵
Remember [problem:1375C]? The solution is to check if $a_1 < a_n$.↵
Tons of people under the contest announcement were excited to explain↵
that this is how to solve the problem. Only a few could explain why↵
it worked.↵
↵
This is also a situation where it is easy for a high-rated author↵
or coordinator to deceive themselves. If you already know such a solution,↵
then it may seem very easy. The implementation is easy and if there is↵
a clean observation you have to check, making that observation seems↵
easy in hindsight. And the large number of solves in the contest ↵
"confirms" that it is easy. But in fact, the problem is only easy↵
to guess, not easy to solve.↵
↵
In the good old days it was not seen as a big violation if pretests↵
were weak. It was normal. Right now weak pretests cause an uproar↵
because people are not expecting it. If weak pretests were the norm,↵
it would not be such an issue.↵
↵
Make weak pretests the norm again. It will improve the quality of standings. Thanks.
↵
**Weak pretests discourage guessing.**↵
↵
There are many contestants who only have a faint idea of why their solution↵
works at all. The problem style of recent years has contributed to this.↵
If the solution boils down to "check this elegant condition, answer↵
`YES` or `NO` based on that", then it is very much possible to solve ↵
problems by guessing. Especially with full feedback.↵
↵
Remember [problem:1375C]? The solution is to check if $a_1 < a_n$.↵
Tons of people under the contest announcement were excited to explain↵
that this is how to solve the problem. Only a few could explain why↵
it worked.↵
↵
This is also a situation where it is easy for a high-rated author↵
or coordinator to deceive themselves. If you already know such a solution,↵
then it may seem very easy. The implementation is easy and if there is↵
a clean observation you have to check, making that observation seems↵
easy in hindsight. And the large number of solves in the contest ↵
"confirms" that it is easy. But in fact, the problem is only easy↵
to guess, not easy to solve.↵
↵
In the good old days it was not seen as a big violation if pretests↵
were weak. It was normal. Right now weak pretests cause an uproar↵
because people are not expecting it. If weak pretests were the norm,↵
it would not be such an issue.↵
↵
Make weak pretests the norm again. It will improve the quality of standings. Thanks.