Question

How can I build a recursive function in python?

Answer 1

I'm wondering whether you meant "recursive". Here is a simple example of a recursive function to compute the factorial function:

def factorial(n):
    if n == 0:
        return 1
    else:
        return n * factorial(n - 1)

The two key elements of a recursive algorithm are:

• The termination condition: n == 0
• The reduction step where the function calls itself with a smaller number each time: factorial(n - 1)