Problem 194. Clockwise or Counterclockwise

Created by Alfonso Nieto-Castanon

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Last Solution submitted on Jul 13, 2023

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Alfonso Nieto-Castanon on 2 Feb 2012

added more samples to the test

David Verrelli on 21 Jun 2018

Hello, Alfonso Nieto-Castanon. This is a very nice problem. It was interesting to see the variety of approaches used to solve it. It was also interesting to notice a few submissions failed your added test cases from circa Dec 2017. Do you allow for self-intersecting polygons, as per https://en.wikipedia.org/wiki/Polygon ?
I suspect a common solution tactic will fail badly when faced with self-intersecting polygons. —DIV

David Verrelli on 21 Jun 2018

...On second thought, maybe there's no consistent definition of CW/CCW for self-intersecting polygons, such as figure-eight or bow-tie ("cross-quadrilateral") shapes.

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Problem 194. Clockwise or Counterclockwise

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Problem 194. Clockwise or Counterclockwise

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