It contradicts itself:
Quote:
No two houses of the same colour are next to one another.
Quote:
Mr Green lives in a brown house one street over from Mr Red who lives in a black house.
Quote:
Mr Burgandy who looks like Mr Red but isn't related lives in a black house next door to Mr Red and Mr Black who lives in a yellow house next to Mr Brown.
So Mr Red and Mr Burgundy are neighbors and both have black houses, yet no two houses side by side are the same color?