| № | Пользователь | Рейтинг |
|---|---|---|
| 1 | tourist | 4009 |
| 2 | jiangly | 3823 |
| 3 | Benq | 3738 |
| 4 | Radewoosh | 3633 |
| 5 | jqdai0815 | 3620 |
| 6 | orzdevinwang | 3529 |
| 7 | ecnerwala | 3446 |
| 8 | Um_nik | 3396 |
| 9 | ksun48 | 3390 |
| 10 | gamegame | 3386 |
| Страны | Города | Организации | Всё → |
| № | Пользователь | Вклад |
|---|---|---|
| 1 | cry | 164 |
| 1 | maomao90 | 164 |
| 3 | Um_nik | 163 |
| 4 | atcoder_official | 160 |
| 5 | adamant | 159 |
| 6 | -is-this-fft- | 158 |
| 7 | awoo | 157 |
| 8 | TheScrasse | 154 |
| 8 | Dominater069 | 154 |
| 8 | nor | 154 |
Problem for you for today's evening:
You are given DAG with N < = 1000 vertexes and M < = 10000 edges. Vertex 0 is starting vertex and vertex 1 is goal vertex. Set weights to edges from {1, 2} in that way that all paths from start to goal will have the same distance or print "NO" if it's not possible.
Can I submit this problem or download tests somewhere? I have an idea, but I can't prove it.
it's problem 241E
A similar problem also appeared in a previous world finals where you could increase the weights on edges and you had to find the minimal increase required.
Fare and balanced — Stockholm 2009
https://icpcarchive.ecs.baylor.edu/index.php?option=com_onlinejudge&Itemid=8&category=43&page=show_problem&problem=2450
Thanks, I didn't know that.
I found pretty code from gawry — 2616676
I don't understand one thing.
How do we know which value (d[a[i]] or d[b[i]]) we should change? I understand constraints and I know it works (he got Accepted :)), but it seems to me unclear. Can anybody help me?
Lines:
We change whichever value is on the right side of the inequality. The code is essentially running Bellman-Ford, so the change can be thought of as an edge relaxation.