Блог пользователя sophisticated1

March cook off problem
Автор sophisticated1, 9 лет назад, По-английски

http://www.codechef.com/COOK56/problems/STRAB/

Can someone explain the dp approach except the one given in the editorial ? Also if someone know similar problems , please provide the link :) .

Теги dp
  • Проголосовать: нравится
  • -3
  • Проголосовать: не нравится

»
9 лет назад, # |
  Проголосовать: нравится +5 Проголосовать: не нравится

In fact, you don't need dp in this problem.

Let's count the following thing (just using a loop over bitmasks): how many there are strings of length L than consist only of A and B and are good (not hated, i. e., don't contain any hated subword).

Now let's iterate over all possible positions of non-AB characters (again as a loop over bitmasks). Obviously, if there is any hated word, it will be between two two consecutive non-AB characters. So we can use the thing we calculated earlier to fill all characters between non-AB ones.

→ Ответить
  • »
    »
    9 лет назад, # ^ |
    ← Rev. 2   Проголосовать: нравится 0 Проголосовать: не нравится

    thanks ,it will be very helpful if you can you refer someone's implemented code ? sorry to bother , i got it :).

    → Ответить
  • »
    »
    9 лет назад, # ^ |
      Проголосовать: нравится 0 Проголосовать: не нравится

    Nice solution, and it seems to be O(n2n) too (don't know why you got downvoted). Why is it not in the editorial?

    → Ответить