https://codeforces.com/contest/1175/submission/238928196 For judging whether an array of length n is a 1~n permutation, I judged its sum{i^1} sum{i^2} sum{i^3} sum{i^4} and passed. Can anyone hack this solution or prove it correct? please help me :(
→ Pay attention
→ Streams
→ Top rated
| # | User | Rating |
|---|---|---|
| 1 | tourist | 3845 |
| 2 | jiangly | 3707 |
| 3 | Benq | 3630 |
| 4 | orzdevinwang | 3573 |
| 5 | Geothermal | 3569 |
| 5 | cnnfls_csy | 3569 |
| 7 | jqdai0815 | 3532 |
| 8 | ecnerwala | 3501 |
| 9 | gyh20 | 3447 |
| 10 | Rebelz | 3409 |
→ Top contributors
| # | User | Contrib. |
|---|---|---|
| 1 | maomao90 | 171 |
| 2 | adamant | 163 |
| 3 | awoo | 161 |
| 4 | nor | 152 |
| 5 | maroonrk | 151 |
| 5 | -is-this-fft- | 151 |
| 7 | TheScrasse | 148 |
| 8 | atcoder_official | 146 |
| 9 | Petr | 145 |
| 10 | pajenegod | 144 |
→ Find user
→ Recent actions
Codeforces (c) Copyright 2010-2024 Mike Mirzayanov
The only programming contests Web 2.0 platform
Server time: Jun/26/2024 21:49:55 (g1).
Desktop version, switch to mobile version.
Supported by
It's incorrect.
Try this:
Maybe it will be difficult to construct a counterexample if you compute powers up to like $$$100$$$ and do some hashing.