Please suggest an approach to solve this problem. (Problem Link)
→ Обратите внимание
→ Трансляции
→ Лидеры (рейтинг)
| № | Пользователь | Рейтинг |
|---|---|---|
| 1 | tourist | 4009 |
| 2 | jiangly | 3773 |
| 3 | Radewoosh | 3646 |
| 4 | ecnerwala | 3624 |
| 5 | jqdai0815 | 3620 |
| 5 | Benq | 3620 |
| 7 | orzdevinwang | 3612 |
| 8 | Geothermal | 3569 |
| 8 | cnnfls_csy | 3569 |
| 10 | gyh20 | 3447 |
| Страны | Города | Организации | Всё → |
→ Лидеры (вклад)
| № | Пользователь | Вклад |
|---|---|---|
| 1 | awoo | 161 |
| 2 | maomao90 | 160 |
| 3 | cry | 158 |
| 4 | atcoder_official | 156 |
| 4 | nor | 156 |
| 6 | -is-this-fft- | 155 |
| 7 | maroonrk | 154 |
| 8 | adamant | 153 |
| 8 | Um_nik | 153 |
| 10 | djm03178 | 146 |
→ Найти пользователя
→ Прямой эфир
Codeforces (c) Copyright 2010-2024 Михаил Мирзаянов
Соревнования по программированию 2.0
Время на сервере: 02.09.2024 23:07:04 (g1).
Десктопная версия, переключиться на мобильную.
При поддержке
Firstly we have to convert the tree queries into array queries. We can perform a dfs and using start and end times , convert the tree to an array. Then each subtree is a range l to r in the array. Now according to the question we have to count the nodes in the subtree rooted at X with value between l to r. That is a range query in array which can be handled using segment tree.
According to me, it was required to run BFS/DFS from node x and check the heights of all nodes in subtree to be in range [L,R]. I constructed a directed graph and followed this approach which gave me WA. Can you tell why this approach is wrong?