Codeforces Round #893 (Div. 2) Editorial

Revision en18, by pakhomovee, 2023-08-16 00:48:46

We hope you liked our problems!

1858A - Buttons

Tutorial
Code

1858B - The Walkway

Tutorial
Code

1858C - Yet Another Permutation Problem

Tutorial
Code

1858D - Trees and Segments

Tutorial
Code

1858E2 - Rollbacks (Hard Version)

Tutorial
Code

Note: At about 20 minutes into the round one of our testers (SomethingNew) came up with a linear solution for problem E2, and jiangly implemented the same solution shortly after the contest! For further details, see 219001999. The main idea (as jiangly pointed out in the comments) is that we can use prefix sums instead of the Fenwick tree.

History

Revisions

Rev. Lang. By When Δ Comment
ru9 pakhomovee 2023-08-16 00:57:15 22 Мелкая правка: '];\n r.push_back(1 - d);\n ' -> '];\n r.insert(r.begin(), 1 - d);\n '
en18 pakhomovee 2023-08-16 00:48:46 22 Tiny change: '];\n r.push_back(1 - d);\n ' -> '];\n r.insert(r.begin(), 1 - d);\n '
ru8 pakhomovee 2023-08-15 21:11:33 12 Мелкая правка: 'ментариях)~--- это то, ' -> 'ментариях) - это то, '
ru7 pakhomovee 2023-08-15 21:11:08 18 Мелкая правка: 'ачи E2, а jiangly написал т' -> 'ачи E2, а [user:jiangly] написал т'
ru6 pakhomovee 2023-08-15 21:10:53 412
en17 pakhomovee 2023-08-15 21:08:33 1 Tiny change: 'er details see [subm' -> 'er details, see [subm'
en16 pakhomovee 2023-08-15 21:07:49 3 Tiny change: '*Note:** After about 20 ' -> '*Note:** At about 20 '
en15 pakhomovee 2023-08-15 21:07:30 417
ru5 pakhomovee 2023-08-15 20:44:52 2
en14 pakhomovee 2023-08-15 20:41:36 2
en13 pakhomovee 2023-08-15 20:06:22 34 Tiny change: ');\n\n sort(r.begin(), r.end());\n\n ' -> ');\n\n '
ru4 pakhomovee 2023-08-15 20:05:55 33 Мелкая правка: ');\n\n sort(r.begin(), r.end());\n\n ' -> ');\n\n '
en12 pakhomovee 2023-08-15 19:44:49 12210
ru3 pakhomovee 2023-08-15 19:44:14 1 (опубликовано)
ru2 pakhomovee 2023-08-15 19:43:17 8087
en11 pakhomovee 2023-08-15 19:39:50 1 (published)
en10 pakhomovee 2023-08-15 19:38:48 145
en9 pakhomovee 2023-08-15 19:36:52 33
en8 pakhomovee 2023-08-15 19:36:22 42
en7 pakhomovee 2023-08-15 19:35:45 80
en6 pakhomovee 2023-08-15 19:34:49 5
en5 pakhomovee 2023-08-15 19:32:54 31
en4 pakhomovee 2023-08-15 19:31:41 70
en3 pakhomovee 2023-08-15 19:30:17 7022
en2 pakhomovee 2023-08-15 19:27:58 8768
ru1 pakhomovee 2023-08-15 19:22:49 813 Первая редакция перевода на Русский (сохранено в черновиках)
en1 pakhomovee 2023-08-15 19:22:23 800 Initial revision (saved to drafts)