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Discussion of Problem 1578. Mammoth Hunt

Proof
Posted by andreyDagger 11 Jun 2022 17:48
Why can we always choose the farthest point?

Suppose the opposite. Let we have 3 adjacent points in our way, which make obtuse angle. Let's call them A, B and C. angle ABC is obtuse, that means that |AC|>|AB| and |AC|>|BC|. But that's impossible because our algorithm chooses the farthest point, but B is not the farthest, C is further than B. Contradiction.

Edited by author 11.06.2022 17:49

Edited by author 11.06.2022 17:49