HCW '19 Team Round Editorial

Revision en1, by low_, 2019-07-22 15:29:38

This is an editorial blog for HCW 19 Team Round (ICPC format). Any further question can be asked in the comments, I'll try to answer all the questions. Please, do not private message or email me, your question could be the same as others', and I really hate to answer one question multiple times. >:(

102279A - Amsopoly Simple Version

Author: low_.

To solve the problem, you'll only need to note that in $$$(N+1)$$$-th turn: Seo moved through exactly $$$(N+1)*V_s$$$ property, that is exactly $$$V_s$$$ full round of the board, so that he end up in $$$1$$$ afterwards. The same happens with B21 and Lowie. After that, the game keeps repeating itself.

We can conclude that: if there isn't any event of one paying other in the first $$$3*(N+1)$$$ turns, it will never happen, so we can output $$$3000000000$$$. Otherwise, we can find the first event of it by brute force in $$$O(3*(N+1))$$$ time complexity.

Solution

102279D - Dahlia The Champion

Author: low_.

Dahlia can only reach targets in the circle of radius $$$R$$$ around her. But the trick here is she only pull one target in each direction she throw her arm to.

Here is the test that some may failed:

Trick Test

History

 
 
 
 
Revisions
 
 
  Rev. Lang. By When Δ Comment
en7 English low_ 2019-07-28 18:58:11 2206 (published)
en6 English low_ 2019-07-24 20:19:10 804
en5 English low_ 2019-07-24 18:11:46 3891
en4 English low_ 2019-07-23 21:25:08 160
en3 English low_ 2019-07-23 21:17:48 650 000
en2 English low_ 2019-07-23 21:07:07 4606 Tiny change: '.,$[1, N-N%2]$, $[1, ' -> '.,$[1, N-N \_ MOD \_ 2]$, $[1, '
en1 English low_ 2019-07-22 15:29:38 1588 Initial revision (saved to drafts)