Coloring
Source: Chinese National Olympiad 2009 P5
January 10, 2009
combinatorics proposedcombinatorics
Problem Statement
Let be a convex polygon each of which sides and diagnoals is colored with one of distinct colors. For which does: there exists a coloring method such that for any three of colors, we can always find one triangle whose vertices is of ' and whose sides is colored by the three colors respectively.