Factorial Python

Question

How to calculate factorial using loop.when should we use iteration vs recursion? Is performance different

Answer 1

D1M1TRIЯ ,

Don't give readymade code...let them try themselves...

And Ariya try it by yourself and share your code link here if you face issues...
Don't expect for readymade code

Answer 2

def factorial_recursive(n):
if n < 0:
return "Factorial is not defined for negative numbers"
elif n == 0 or n == 1:
return 1
else:
return n * factorial_recursive(n - 1)

# Example usage
print(factorial_recursive(5)) # Output: 120

here is a recursive aproach

Answer 3

Ariya
👉 When to use Iteration or Recursion
For simple algorithms where performance is not critical, either can be used.
For more complex algorithms, sometimes iteration or recursion will be easier to read and follow the logic.
Example - Recursion is often used for binary tree traversal.

👉 Performance
Iteration (looping) will perform better than most forms of recursion.
Tail-end recursion is the one form of recursion which typically has performance equal to iteration.
So if you do use recursion, try for tail-end.

https://www.geeksforgeeks.org/tail-recursion/

https://stackoverflow.com/questions/33923/what-is-tail-recursion