Let's discuss the solutions.
How to solve B?
I remember back in 2004-2005 Usaco had blue-orange-green sections and the green division problems were quite rich of flow poblems. Also they had nice Editorials as usual. In CF I saw couple of threads asking for old Usaco problems and people were referring to many other sites. I was wondering if you have link/archive of those old Editorials.
We are inviting you to participate in ACM ICPC Dhaka Regional 2014 Online version. We are using a cloud based judging system to host the contest. The system has already been used in the ACM ICPC 2013 Dhaka Preliminary round online contest with the participation of 800+ teams. The system can be accessed at www.codemarshal.com. Please note that, for the time being you will need to create a separate registration at CodeMarshal (The UVa ID and password will not work). The contest is at: Sunday, December 7, 2014 at 9:00:00 AM UTC.
I am not sure if i am missing something in the solution presented here.
Consider this example: say we start at s, the attraction at s+1 is 1, at s+2 is 2, at s+3 is 50 and at s-100 is 100. In other places it is 0. Value of d is 107.
The optimal solution is: take 1, 2 and 100. But if I follow the solution at analysis, it will be 100 if we go left first and 53 if we go right first. The reason is, in the optimal solution we spend 4 days right side (move right + attraction). But if f() is computed independent of the fact that we will move left later then f(4) = s+3 and we gain 50 but the optimal solution will say don't go that far to s+3 rather you collect 1 and 2 in 4 days and move left. So it is not true that f(t) be always the optimal point if we had the reduced problem.
Can any one explain where I am going wrong?
I heard that one can find good books on Mathematics/Programming (Programming contest/olympiad, text book, linear algebra, olympiad mathematics, geometry) in Russia. Are they available in english? If so how is the price comparing to the price online? Can any one suggest any good books or book store at Ekaterinburg?
There will be online version of the ACM ICPC Phukhet Regional 2013 tomorrow 14:00UTC time. It will be 5 hour contest. You are cordially invited to participate in the contest. Hope you will enjoy the set!
Here is the contest link
Three popular algorithms for string related problems are: Suffix Array, Suffix Automaton and Suffix Tree. So what are the advantages/disadvantages of each of these? Is there any types of problems which is easy to tackle by one of these 3, but not by other 2? Let's gather these types of information in this post. :)
I thought this discussion will be helpful for many :)
I use C++. I use Visual C++ 6.0 which comes with visula studio 6.0. This has excellent debugging and the editor looks quite nice to me, no need to create project. But the problem is, while debugging i cant see the vector elements (same for other STL elements). Another problem is, __int64, i face lot of trouble for topcoder contests. Other editor like netbeans, eclipse and higher versions of visual studio etc requires creation of project, I do not like this. Spending time for creating project is just waste of time :P
For Java, Jcreator / JBuilder seems nice to me. They don't need project creation. But it seems to me that they are somewhat slower than C++, though some leading coders use java.