This section TEXT introduces the content of computational geometry. Regarding the content of computational geometry, we need to elaborate separately. The difficulty is convex hull.
first question:
The main idea of the topic: Given a number of points counterclockwise, judge whether these points can form a polygon, and given an observation point, find the observable line segment at this point
Algorithm: Enumeration + Computational Geometry
This topic is very tangled. I spent half a day studying the code of MAIGO. I understood it roughly, but I couldn't fully digest it.
Question 2: American Heritage
Algorithm: In-order traversal
Question 3: Electric Fence
Algorithm: Pick's Theorem
Fourth question: Raucaus Rockers
Algorithm 1: Enumeration + bit operation + pruning
Algorithm 2: DP (classic)
The following is a well-written program on the NOCOW website, it is worth learning
**The idea of DP is not very clear, only the basic form, it is necessary to study DD_ENGI's "Nine Lectures on Backpack" carefully.
**The foundation of computational geometry is very weak and needs to be strengthened