Almost completely different scores on IMO day 1
Source: ITAMO 2016, Problem 2
May 11, 2016
combinatorics
Problem Statement
A mathematical contest had problems, each of which was given a score between and ( and included). It is known that, for any two contestants, there exists at most one problem in which they have obtained the same score (for example, there are no two contestants whose ordered scores are and , but there might be two contestants whose ordered scores are and ). Find the maximum number of contestants.