Hi everyone. Just posting this blog so we can discuss the solutions to the problems of the 2022-2023 ICPC Latin American Regional Programming Contest.

Mirror on beecrowd: https://www.beecrowd.com.br/judge/en/challenges/contest/751

Mirror on gym: https://codeforces.com/gym/104252

Links to individual problems (PDF files):

G — Gravitational Wave Detector

Auto comment: topic has been updated by DanielB999 (previous revision, new revision, compare).Hi!. In the problem K, the checker is correct?

I made my own checker to verify that the toppings I placed are related and also later check that the number of groups with different toppings is >= k

Link of code: https://ideone.com/JpyUC7

I guess it's because the number of different toppings should be exactly equal to K

By the way, I'm curious about the solution for this problem

This was my solution for problem K:

KThe minimum number of operations is $$$T=\lceil log_2(K) \rceil$$$.

To print a solution, consider a $$$100 \times 100$$$ grid that have the numbers from $$$0$$$ to $$$K-2$$$ written on the first $$$K-1$$$ cells of the rows with odd index (except in the last column) and the rest of cells have written $$$2^T-1$$$ on them. For example, for $$$K=102$$$:

The idea is to use the machine during the $$$i$$$-th operation on the cells that have the $$$i$$$-th bit set. Every cell is adjacent to at least one cell with the number $$$2^T-1$$$, so the cells used during each operation will form a connected component, and we will have $$$K$$$ types at the end.

Wow, very beautiful solution

Thanks!

F for my reading comprehension in the regional XD

I decided to write an unofficial editorial of the contest. It contains hints/solutions of all the problems. Feel free to check it here :)

In problem A, we are told that $$$x_i, y_i \neq i$$$ and $$$x_i \neq y_i$$$ but when verifying this condition with an assert, it is not fulfilled in some cases

Yep, sadly test case 5 contains $$$x_i == y_i$$$.