We will hold AtCoder Regular Contest 198 (Div. 2).
- Contest URL: https://atcoder.jp/contests/arc198
- Start Time: http://www.timeanddate.com/worldclock/fixedtime.html?iso=20250525T2100&p1=248
- Duration: 120 minutes
- Number of Tasks: 5
- Writer: PCTprobability
- Tester: Nyaan, maspy
- Rated range: 1200 ~ 2399
The point values will be 300-500-700-700-900.
We are looking forward to your participation!
What is the idea behind D? I was thinking of some dsu-based approach, but couldn't fit in the TL.
use dsu without hash is ok. You can see my submission https://atcoder.jp/contests/arc198/submissions/67419508
B is cancer for me
Instead of stronger cloudflare AtCoder need stronger sample cases!
Part of the difficulty in these problems (specially in B and C) is to create corner cases in order to break your solution ideas, with stronger samples it would just be a guessing game until it passes the samples.
D is very easy for its position
shit B, easy D
B even worse than shit. My toilet will vomit if it see B.
Supposedly the constraints in problem E were set to cut $$$O(2^N N^2)$$$ solutions. I used a similar idea to online convolution, but with OR convolution instead. It passed in $$$4.5$$$ s :).
My submission
In editorial of D I find
But I can't find the definition of $$$M$$$ in the Problem or Editorial. Can you fix it or I'm wrong?
I think $$$M$$$ is the number of ones in the matrix $$$A$$$. So in the worst case $$$M$$$ can be up to $$$N^2$$$.
C was awesome, kudos to the setters
for B, this pattern works too. I used this
2101......2101101.....1012020.....200......0Submission
I can't understand this hate for B.... I mean it was decent, no?
I agree. Considering corner cases is interesting, I think.
I couldn't even understand the English statement of B. I interpreted it as there are $$$A_i$$$ numbers that is no less than $$$\min(A_{i-1},A_{i+1})$$$, no more than $$$\max(A_{i-1},A_{i+1})$$$ and less than $$$A_i$$$. Unluckily, the sequece in the sample also fits this condition. It wasn't until I changed language to Japanese that I understood the problem.
I can feel for you. I also couldn't understand at first glance and when asked about it in clarification, they cleared it to me and I understood it