Quicksort and chill I began holding some weekly student workshop at Imperial College London and I find some of the material presented useful for Codeforces community, so I will also post it here. So, enjoy! Quicksort --------- We already discussed some cool sorts such as mergesort that work in O(N log N). We want you to learn not “a sort algorithm”, but the ideas behind some of them. A technique that works many times is finding redundancies in problems. We will illustrate this by trying to build quicksort out of insertion sort. Insertion sort takes each element and puts it in the right place. Take the next example: ( first array is the sorted one that is being constructed and the second is the remainings from the initial array ) [cut] ~~~~~ [] [ 2 , 3 , 1 , 2 , 5 ] → [ 2 ] [ 3 , 1 , 2 , 5 ] → [ 2 , 3 ] [ 1 , 2 , 5 ] → [ 1 , 2 , 3 ] [ 2 , 5 ] → [ 1 , 2 , 2 , 3 ] [ 5 ] → [ 1 , 2 , 2 , 3 , 5 ] [ ] ~~~~~ This seems to work fine, but the array `[ 5 , 4 , 3 , 2 ...

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Teams going to ACM ICPC World Final 2016 With many regionals around the world finished, I think it is time to start collecting teams that are going to World Final this year. Please help me adding information to the tables :) --- Europe ====== | **Region** | **Country** | **University** | **Member 1** | **Member 2** | **Member 3** | | --------- | ----------- | -------------- | ------------ | ------------ | ---------- | | NEERC | Russia | Ural Federal University | [user:Um_nik,2016-05-15] | [user:Umqra,2016-05-15] | [user:Merkurev,2016-05-15] | | NEERC | Russia | SPb State University | [user:Copymaster,2016-05-15] | [user:-XraY-,2016-05-15] | [user:ershov.stanislav,2016-05-15] | | NEERC ...

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Looking for Imperial College London team Hello ! In October I am comming to **Imperial College London** for MSc in computing. I am looking for team to compete at upcomming programming competitions. Last year our team ranked 2nd at national programming competition and ranked in upper half at ACM ICPC CERC (we solved 5/12 problems). I have codeforces rating of ~1800 and TopCoder rating of ~1700. I am pretty relaxed when it comes to programming competitions and believe that chilled team is most important for success. Looking forward to hearing from some team! Erik

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Old/Classical problems on a regional? A time ago, I read this blog: [aleigorithms — ICPC Latin American Regional – 2017](https://aleigorithms.wordpress.com/2017/11/14/icpc-latin-american-regional-2017/) In that blog the author says "This is not an original problem. Is sad to see this kind of problems in an ICPC regional." when are explaining the solution to the problem ([F — Fundraising]( https://icpcarchive.ecs.baylor.edu/index.php?option=com_onlinejudge&Itemid=8&category=788&page=show_problem&problem=6218)). A weeks ago I was talking with a friend about the 2017 Latin America Regional, and he told me that the problem [I — Imperial roads](https://icpcarchive.ecs.baylor.edu/index.php?option=com_onlinejudge&Itemid=8&category=788&page=show_problem&problem=6215) is a classical/old question and not original and it's linked as a recomended problem on a tutorial. I looked a while trying to find the "original" problems and the tutorial, but until now I cannot find it. Somebody know where I can find t...

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How to solve this GYM Problem? I am trying with Articulation point + Kruskal.... [Imperial roads](http://mirror.codeforces.com/gym/101889/attachments) That's why my code becomes so large and i can't fix bug. Is there any other approach? Or give me corner case for my [code](https://paste.ubuntu.com/p/7X5t8QK5G2/)

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