The “Windmill” Problem on the 2011 International Mathematical Olympiad [video]

Re:The “Windmill” Problem on the 2011 International Mathemat... by jerf on Thursday October 17, 2019 @02:01PM (#21284718)

There's maybe a step or two's worth of that, then the answer. The video is not explicitly structured as a set of clues, it only accidentally half-does that because it builds up to the answer mathematically, but I would not say the steps are "even" in size.

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Re:The “Windmill” Problem on the 2011 International Mathemat... by Tallasatree on Thursday October 17, 2019 @02:48PM (#21285193)

is this in essence a convex-hull problem, except instead of closing, we continue?

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Re:The “Windmill” Problem on the 2011 International Mathemat... by bcyn on Thursday October 17, 2019 @10:22PM (#21288110)

I think he presents a line of reasoning that also helps to formalize why finding a convex hull works.

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Re:The “Windmill” Problem on the 2011 International Mathemat... by AnimalMuppet on Thursday October 17, 2019 @04:18PM (#21285976)

I don't think so. In a convex hull, you only visit points on the hull of the set, not in the interior. In this problem, you visit points in the interior too (if I understand correctly).

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Re:The “Windmill” Problem on the 2011 International Mathemat... by saagarjha on Thursday October 17, 2019 @06:35PM (#21286971)

You get to choose the line so that this circuit is possible. If you didn’t, you’d essentially be able to form a convex hull and thus not visit all the points.

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Re:The “Windmill” Problem on the 2011 International Mathemat... by utopcell on Friday October 18, 2019 @12:01AM (#21288555)

No. In fact, in the end he shows a list of approaches one might think are related but turn out not to be, and computing convex hulls is one of them.

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