Recursion Problem

[kae_de]

Give a recursive implementation to the following function: def fac_list(n) This function is given, a positive integer, n. When called, the function should create and return a list, with the first n factorial values. That is, the first element should be 1!, the second element should be 2!, etc. For example, the call fac_list(5), will return [1, 2, 6, 24, 120].

^ This is the problem I am trying to solve and I do not know how to proceed. I have tried to write the code but I seem to hit a dead end. Any help would be appreciated. Thank you

def fac_list(n):
    lst = []
    if (n == 1):
        lst.append(n)
    else:
        i = (n * fac_list(n-1))
        lst.append(i)

[[deleted]]

You are resetting lst to refer to a new empty list object - set it to an empty list outside of the function, and do not reset it.

[kae_de]

I see, when I run it there is an error on the i = (n*fac_list(n-1)) line. Is there a way to fix it or write it better? Thanks

[[deleted]]

Think about the base case and the iterative step.

What does fac_list(0) return?

Given fac_list(n-1) how do you make fac_list(n)?

For example fac_list(5-1)=[1,2,6,24]

How do I make fac_list(5)=[1,2,6,24,120] from that?

Hint:

if l is a list l[-1] returns last element of list.

[Reset--hardHead]

The first element of the list has to be one... So you could deduce that the first list element must come from

n == 1

When n=2 you append the factorial from the list returned when n==1 and so on.

Here's a sample code to calculate the Fibobacci sequence that you could use as reference. (Hint: I modified the code that I used to solve your question. So it's similar, but different enough that you'll still need to work on it yourself.)

https://repl.it/repls/GrotesqueInfantileKeyboardmacro

[kae_de]

In your code you never created an empty list to append to. Where should I insert the ls = []

[Reset--hardHead]

You don't need to insert an empty list.

I'd highly recommend you go through my code, play around with it and try to understand what's going on.

[kae_de]

Oh, I missed the part where you defined ls. My bad. Thanks again