def hypercube(k):
'''
Returns the $k$-dimensional hypercube graph. See West, p. 36,
example 1.3.8.
'''
G = completeGraph(1)
P2 = completeGraph(2)
while k:
G = graphCartesianProduct(G, P2)
k -= 1
return G
def gridGraph(m, n):
return graphCartesianProduct(path(m), path(n))
