| № | Пользователь | Рейтинг |
|---|---|---|
| 1 | tourist | 4009 |
| 2 | jiangly | 3839 |
| 3 | Radewoosh | 3646 |
| 4 | jqdai0815 | 3620 |
| 4 | Benq | 3620 |
| 6 | orzdevinwang | 3612 |
| 7 | Geothermal | 3569 |
| 8 | ecnerwala | 3494 |
| 9 | Um_nik | 3396 |
| 10 | gamegame | 3386 |
| Страны | Города | Организации | Всё → |
| № | Пользователь | Вклад |
|---|---|---|
| 1 | maomao90 | 164 |
| 2 | Um_nik | 163 |
| 3 | atcoder_official | 159 |
| 4 | cry | 158 |
| 4 | -is-this-fft- | 158 |
| 6 | awoo | 155 |
| 7 | adamant | 154 |
| 7 | nor | 154 |
| 9 | TheScrasse | 153 |
| 10 | Dominater069 | 152 |
how to solve this problem
You have directed acyclic forest. Every node except root nodes have 1 parent.
Query 1: Change parent of one node or make it a root node(it is guaranteed graph will not have cycle)
Query 2: input a node and output the root of the tree that node is in.
Number of nodes = 2e5 Number of queries = 2e5
