ENG  RUSTimus Online Judge
Online Judge
Problems
Authors
Online contests
About Online Judge
Frequently asked questions
Site news
Webboard
Links
Problem set
Submit solution
Judge status
Guide
Register
Update your info
Authors ranklist
Current contest
Scheduled contests
Past contests
Rules
back to board

Discussion of Problem 1747. Kingdom Inspection

Why for n=4 answer is 30?
Posted by bsu.mmf.team 23 Jan 2010 14:08
In my opinion, for n=4 the correct answer is 20 if I understood the condition of the problem correctly, i.e for n=3 there are exists 2 ways:
123231 and 132321. Please, explain me my mistake if I'm wrong.
Re: Why for n=4 answer is 30?
Posted by Lezhankin Petr [Ufa] 23 Jan 2010 18:52
12324341
12342341
12342431
12343241
12343421
12423431
12432341
12432431
12434231
12434321
13234241
13242341
13242431
13243241
13243421
13423241
13423421
13424231
13424321
13432421
14232341
14232431
14234231
14234321
14243231
14323241
14323421
14324231
14324321
14342321
Re: Why for n=4 answer is 30?
Posted by bsu.mmf.team 30 Jan 2010 02:03
Oh! Now I understood my mistake. Thank you!