Udacity Design of Computer Analysis

shuffler.py

def swap(deck, i, j):
    "Swap elements i and j of a collection."
    print 'swap', i, j
    deck[i], deck[j] = deck[j], deck[i]

def shuffle2(deck):
    "A modification of my teacher's algo"
    N = len(deck)
    swapped = [False] *	N
    while not all(swapped):
      	i, j = randrange(N), randrange(N)
      	swapped[i] = True
	swap(deck, i, j)

def shuffle3(deck):
    "An easier modification of my t's algo"
    N =	len(deck)
    for	i in range(N)
      	swap(deck, i, randrange(N))