| # | User | Rating |
|---|---|---|
| 1 | tourist | 3993 |
| 2 | jiangly | 3743 |
| 3 | orzdevinwang | 3707 |
| 4 | Radewoosh | 3627 |
| 5 | jqdai0815 | 3620 |
| 6 | Benq | 3564 |
| 7 | Kevin114514 | 3443 |
| 8 | ksun48 | 3434 |
| 9 | Rewinding | 3397 |
| 10 | Um_nik | 3396 |
| # | User | Contrib. |
|---|---|---|
| 1 | cry | 167 |
| 2 | Um_nik | 163 |
| 3 | maomao90 | 162 |
| 3 | atcoder_official | 162 |
| 5 | adamant | 159 |
| 6 | -is-this-fft- | 158 |
| 7 | awoo | 155 |
| 8 | TheScrasse | 154 |
| 9 | Dominater069 | 153 |
| 10 | nor | 152 |
A hard problem from Vietnam Olympiad in Informatics for 9-grader [Part 2]
English version:
The first problem is similar to Problem G — Inverse Factorial in 2016 ICPC North American Qualifier Contest; however, there is a twist: if there is no n for the given value n!, you need to output - 1.
I think there is a solution for this problem, but I can not find it :)
By the way, a gifted 9-grader in Vietnam has no idea about FFT anything similar to that.
