Since usually there's no editorial for this contest (already on Gym), I wrote explanations to my team's (thank you leoanjos and gabmei) solutions during the official mirror/bracket that retired people can participate, they're available at https://github.com/tfg50/competitive-programming-tutorials/blob/main/ICPC/Latin%20america/2025%20Brazil%20First%20Phase/editorial.pdf. Solutions have been posted on the same repository. Feel free to share your opinions on the problems, ask questions, and perhaps comment on some of the alternative solutions that I didn't mention or explain.