Hello, Codeforces!

We are glad to invite you to participate in Codeforces Round 1048 (Div. 1) and Codeforces Round 1048 (Div. 2) on Sep/08/2025 17:35 (Moscow time).

The round will be rated for everyone. You will be given 6 problems and 3 hours to solve them in both divisions. Some problems will be divided into subtasks.

The problems were authored and prepared by installb, wjy666, tarjen, StarSilk and 2014CAIS01.

We would like to thank:

• maomao90 for his great coordination.
• Alexdat2000 for Russian translation.
• Um_nik, EvenImage and SSerxhs for red-black testing.
• A_G, -skyline- and __baozii__ for red testing.
• fishy15, oolimry, Boboge, Nanani, shstyle. and Tobo for orange testing.
• qsmcgogo and Retired_Zhisheng for purple testing.
• Husqqqq for blue testing.
• jellybean259 for green testing.
• akqxolotl for grey testing.
• MikeMirzayanov and KAN for the great platforms.

The scoring distribution is below.

• Div. 2: $$$ 500-1000-1500-2250-(2250+750)-3500 $$$
• Div. 1: $$$ 500-1250-(1250+750)-2500-(2750+1500)-4250 $$$

Good luck to everyone! (=^･ω･^=)

UPD：Unfortunately, it was discovered very lately (2 hours after the contest began) that the statement of div2D/div1B was missing an important condition. The correct statement should include the line "The operation 2 can only be applied at most once." The statement will be corrected soon.

We believe this issue affected many participants of this round, and therefore we have to declare this round unrated. We sincerely apologize for this mistake.

https://mirror.codeforces.com/blog/entry/146176 please refer to this blog for more information on why we decided to make the round unrated, and further elaborations on how this accident happened. We are deeply sorry for disappointing everyone, and we hope for your understanding.

UPD2: Here's the editorial: https://mirror.codeforces.com/blog/entry/146172