Hey All!
Topcoder SRM 766 is scheduled to start at 21:00 UTC -4, Sept 10, 2019.
Problem Writer:misof
Registration is now open for the SRM in the Web Arena or Applet and will close 5 minutes before the match begins.
Good luck to everyone!
Topcoder Java Applet | Next SRM 767 — Sept 18
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| Match Results | (To access match results, rating changes, challenges, failure test cases) |
| Problem Archive | (Top access previous problems with their categories and success rates) |
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How to solve 500?
read the editorialIt's possible to visit a connected component without any risks. Let's arbitrarily root the tree. Consider the following algorithm: you're in vertex $$$v$$$, visit its subtree and return to the parent of $$$v$$$ (leave the subtree). This is done by visiting the subtree and ending in some son of $$$v$$$ (or doing nothing if $$$v$$$ is a leaf), then moving 2 edges up. How to do that? Pick some son $$$s$$$ of $$$v$$$ and recursively apply this algorithm on all sons of $$$s$$$ — move from $$$v$$$ to a son of $$$s$$$, visit its subtree and return to $$$s$$$; if there are unvisited sons of $$$s$$$, don't stop in $$$s$$$, but move further to some other son of $$$s$$$ (notice that the last step of "return" was just by moving 2 edges, so you can still add one), and otherwise, just end by moving to $$$s$$$. Repeat with all other sons of $$$v$$$; you're always moving from a son of $$$v$$$ to a son of a son of $$$v$$$, so that's again at most 3 edges.Want to participate but can't. Next two rounds are on weekday :(
Hi, still waiting for the editorial. :-)
Looking at the editorial link, since many editorials are not there, maybe it can just say "No editorial will be provided"? IF there is no plan to offer one, then we will know instead of needlessly checking.
The problems by misof were very nice (Division 2). I really liked the harder first problem, and that the first and second were implementation-heavy, and third required some algorithm knowledge. That seems like a good formula for Division 2. Makes it interesting and doable for both beginners and "regulars" like me, and the heavier 1000 keeps it interesting for advanced guys playing in their first (and only) time in Div2.
Couple other TopCoder feedbacks:
Are there any plans for another "combined" SRM? I really liked that idea.
There are important broken links on the tco19 site, like https://tco19.topcoder.com/algorithm
Thanks!
Unrelated plug: My CodeForces blog archive is at codeforces-blogs.web.app
SRM 766 Editorial
Thanks, that is nice! Who wrote that, and is it part of a larger "Editorial" collection?