Want to print each iteration of factorial program

[sbabu]

Hi Mr.JefSummers,

I am a self learner. I gathered lot of material and started working on them. What I found is in all of them they just teach syntax with 1 or 2 examples. And give lot of exercises (some will give solutions using techniques which were not discussed).

How do I develop the mindset to think several steps a head, using different scenarios? Are there any exercises to train the brain?

How long did it take for you to become comfortable with basic coding? I am putting 4 hrs every day for the past 2 months. It's taking lot time.

Any advise appreciated.

Thanks again.

---

As I told - one way is to use memoization. It seems to me that if you are 'told' then it's homework therefore I provide a solution which has caveats and may not pass automated test system:

def factorial(n, d={0:1, 1:1}): 
    if n < 0: 
        raise ValueError('No factorials for negative numbers!') 
    if n in d: 
        print(f'n is {n}, carry over {d[n]}, this is base case') 
        return d[n] 
    else: 
        value = factorial(n-1, d) * n 
        d[n] = value 
        print(f'n is {n}, carry over {n} * {d[n-1]} = {d[n]}') 
        return value

This gives:

>>> factorial(5)                                                                                                        
n is 1, carry over 1, this is base case
n is 2, carry over 2 * 1 = 2
n is 3, carry over 3 * 2 = 6
n is 4, carry over 4 * 6 = 24
n is 5, carry over 5 * 24 = 120
120
>>> factorial(0)
n is 0, carry over 1, this is base case
1
>>> factorial(-5)
/.../
ValueError: No factorials for negative numbers!
# But! Second time in same session:
>>> factorial(5)                                                                                                       
n is 5, carry over 120, this is base case
120
>>> factorial(6)                                                                                                        
n is 5, carry over 120, this is base case
n is 6, carry over 6 * 120 = 720
720

Hi perfringo,

I am a self learner. I gathered lot of material and started working on them. What I found is in all of them they just teach syntax with 1 or 2 examples. And give lot of exercises (some will give solutions using techniques which were not discussed).

How do I develop the mindset to think several steps a head, using different scenarios? Are there any exercises to train the brain?

How long did it take for you to become comfortable with basic coding? I am putting 4 hrs every day for the past 2 months. It's taking lot time.

Any advise appreciated.

Thanks again.