I was solving 1684D - Ловушки of recent contest and have faced with strange thing.
Pls look at two pairs of submissions. (There are very simple code)
In both pairs codes' difference is the same: 'wrong' submission uses lambda function with operator >= instead of > in 'good' submission.
Can it be explained?
| № | Пользователь | Рейтинг |
|---|---|---|
| 1 | jiangly | 3810 |
| 2 | Benq | 3676 |
| 3 | Kevin114514 | 3655 |
| 4 | maroonrk | 3463 |
| 5 | strapple | 3447 |
| 6 | Um_nik | 3387 |
| 7 | heuristica | 3322 |
| 8 | turmax | 3317 |
| 9 | tourist | 3307 |
| 10 | jiangbowen | 3291 |
| Страны | Города | Организации | Всё → |
| № | Пользователь | Вклад |
|---|---|---|
| 1 | Qingyu | 156 |
| 2 | nik_exists | 150 |
| 2 | maspy | 150 |
| 4 | Um_nik | 141 |
| 5 | Errichto | 139 |
| 6 | adamant | 137 |
| 7 | AmShZ | 136 |
| 8 | BledDest | 132 |
| 9 | maroonrk | 131 |
| 10 | qwexd | 129 |
i suppose (i'm not sure of course), that sorting with operator >= is bad because comparator can swap equal elements infinitely (sounds a bit crazy, but seems like there are not other reasons for RE and TL)
https://codeforces.me/blog/entry/70237
Thank you.
if comparator returns true for (a, b) it should return false for (b, a). otherwise it's undefined behavior
Thank you.