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

[lupoalberto]

1- bubblesortOnePass()'s return value is never used, so you don't need to return l.

Yes, you're right, that function was the bubble sort recursive function.
Then i modified it and i transformed it into another non recursive function with only one pass.
So i must remove that condition.

2- Is it good to define a local counter in line 50, then a global counter in line 17?

I did in this way because the variable counter inside the function is "hooked" at the counter variable outside the function.
And every time the recursive function restarts, that variable doesn't come back to zero.
It comes back to zero only when the step of loop outside the function ends and a new step starts.
But i've been coding only for 4 months, so i'm not sure this is an elegant solution.

5- If I had to guess, the problem might be line 29.

mmm.... if i write this list for example:

new = [9,2,8,1,7] 

and i pass it to the bubblesortTwoPass function in this way:

after2pass = bubblesortTwopass(new)
print(after2pass)

Output:
[2,1,7,8,9]

So the algorithm is right.

But i don't understand why if i write:

bubblesortTwopass(new)
print(new)

the output is

Output:
[2,8,1,7,9]

in other words i obtain the bubble sort after only the first pass without the second.