Question

For which value of n are these graph regular ?

(a) Kn (b) Cn (c) Wn (d) Qn

Answer 1

Every vertex in Kn has degree n − 1. Kn has an Euler circuit if n is odd.Every vertex in Cn has degree two. Cn has an Euler circuit for every n.Every vertex except the center of Wn has degree three. Wn has an Euler circuit for no n.Every vertex in Qn has degree n. Qn has an Euler circuit if n is even.