Python Array Rotation

Question

So I am implementing a block swap algorithm in python.

The algorithm I am following is this:

Initialize A = arr[0..d-1] and B = arr[d..n-1] 1) Do following u

Answer 1

I expect that when you pass a slice of a to your recursive call, you're not passing the same variable any more. Try passing a in its entirety and the upper / lower bounds of your slice as additional arguments to your function.

For instance consider this function:

def silly(z):
  z[0] = 2

I just tried the following:

>>> z = [9,9,9,9,9,9]
>>> silly(z)
>>> z
[2, 9, 9, 9, 9, 9]
>>> silly(z[3:])
>>> z
[2, 9, 9, 9, 9, 9]

Where you can see the modification to the slice was not retained by the full array

Out of curiosity, what outputs do you get & what outputs do you expect?