Python Coding challenge - Day 172 | What is the output of the following Python Code?

 

Code:

def fun(x, y):

    if x == 0:

        return y

    else:

        return fun(x - 1, x * y)

print(fun(3, 5))

Solution and Explanation: 

Let's break down the provided Python function fun(x, y) and an example call print(fun(3, 5)):

def fun(x, y):

    if x == 0:

        return y

    else:

        return fun(x - 1, x * y)

print(fun(3, 5))

Function Definition:

The function fun(x, y) takes two parameters, x and y.

Base Case:

The function checks if x is equal to 0. If it is, the function returns y. This serves as the base case for the recursive function.

Recursive Case:

If x is not equal to 0, the function calls itself recursively with x - 1 and x * y.

Recursion:

The function keeps calling itself with a decremented x until x becomes 0, each time multiplying y by the current value of x.

Example Call:

print(fun(3, 5)) calls the fun function with x = 3 and y = 5.

The function first checks if x is 0. Since it's not, it enters the recursive case.

It calls fun(2, 3 * 5), then fun(1, 2 * (3 * 5)), and finally fun(0, 1 * (2 * (3 * 5))).

When x becomes 0, it returns the accumulated value of y, which is 2 * (3 * 5) = 30.

So, the output of print(fun(3, 5)) will be 30.