Can anyone please provide any hint for this problem? Throwing Dice
№ | Пользователь | Рейтинг |
---|---|---|
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 |
Страны | Города | Организации | Всё → |
№ | Пользователь | Вклад |
---|---|---|
1 | cry | 167 |
2 | Um_nik | 163 |
3 | maomao90 | 162 |
3 | atcoder_official | 162 |
5 | adamant | 159 |
6 | -is-this-fft- | 158 |
7 | awoo | 156 |
8 | TheScrasse | 154 |
9 | Dominater069 | 153 |
10 | nor | 152 |
Can anyone please provide any hint for this problem? Throwing Dice
Название |
---|
Let f(n) be the number of ways of throwing dices to get a sum of n, Then consider the last dice throw. It has 6 possibilities 1-6. So f(n) = f(n-1) + f(n-2) + ... + f(n-6).
The recurrence is correct. However, unfortunately, it TLE's. There is hope though. This is a linear recurrence can be computed for arbitrary values of n using fast matrix exponentiation. Here is a geeks for geeks article that illustrates the technique in action https://www.geeksforgeeks.org/find-nth-term-a-matrix-exponentiation-example/
My fav trick in such problems:
1. precalc first 20 values
2. use Berlekamp-Massey algorihm to compute n_th value of Linear recurrence
source: https://mirror.codeforces.com/blog/entry/61306?
another problems:
https://mirror.codeforces.com/contest/392/submission/51596991
https://mirror.codeforces.com/contest/678/submission/51597127