# Pentagon

Author: mathforces
Problem has been solved: 17 times

Русский язык | English Language

Given a convex 2020-gon $M$. Let $k$ be the smallest number of points that can be marked inside $M$ so that inside any pentagon whose vertices are $M$ vertices, there are exactly 3 points from the marked ones. Find the smallest possible value of $k$. (“Inside” means strictly inside, not at the border)