1996 blue and red points - All-Russian MO 1996 Regional (R4) 10.8
Source:
September 23, 2024
geometrycombinatoricscombinatorial geometryColoring
Problem Statement
There are points marked on a straight line at regular intervals. Petya colors half of them red and the rest blue. Then Vasya divides them into pairs ''red'' - ''blue'' so that the sum distances between points in pairs was maximum. Prove that this maximum does not depend on what coloring Petya made.