Bubble sort quiz: why the result is not the same?

[ljmetzger]

Your code seems a little complicated, but I agree with your answers.

For 1,000,000 passes I got the following results using my code:

Output:
Pass 1   1090 counts   Frequency 0.00109
Pass 2   2042 counts   Frequency 0.00204

You do not need two algorithms. You could use something like:

import random
 
def bubble_sort_one_pass(a, pass_number):
    n = len(a)
 
    # Subtract 1 because arrays are '0 based' and Pass 1 uses index 0
    i = pass_number - 1
    for j in range(0, n-i-1):
        if a[j] > a[j+1] :
            a[j], a[j+1] = a[j+1], a[j]
    return(a)

    def generateList():
    L = []
    remaining = [i for i in range(1,41)]
    while len(L) < 40:
        random_N = random.choice(remaining)
        L.append(random_N)
        remaining.remove(random_N)
    return L
 
N = 1000000
totalOnePass = 0
totalTwoPass = 0
for i in range(N):
    L = generateList()
    f = L[19]

    pass_number = 1
    L = bubble_sort_one_pass(L, pass_number)
    if f == L[29]:
        totalOnePass += 1

    pass_number = 2
    L = bubble_sort_one_pass(L, pass_number)
    if f == L[29]:
        totalTwoPass += 1
print("Probability after One Pass is {}".format(float(totalOnePass / N)))
print("Probability after Two Pass is {}".format(float(totalTwoPass / N))) 

Lewis