Apply recursive call to do the following: a) Product of two numbers using repetitive addition

Apply recursive call to do the following:
a) Product of two numbers using repetitive addition

def product(a, b):
    if a < b:
        return product(b, a)
    elif b != 0:
        return a + product(a, b - 1)
    else:
        return 0

a = int(input('Enter 1st number:'))
b = int(input('Enter 2nd number:'))
print('Product of both numbers is:', product(a, b))

Output : 
Enter 1st number: 4
Enter 2nd number: 3

Product of both numbers is: 12

Certainly! The provided Python code defines a function product that recursively calculates the product of two numbers using addition. Here’s a detailed explanation of how the code works:

Explanation

1. Function Definition (def product(a, b):):

• This line defines a function named product that takes two parameters, a and b, which are the two numbers whose product needs to be calculated.

1. Swap if a is Less Than b (if (a < b):):

• If a is less than b, the function calls itself with the arguments swapped (return product(b, a)). This ensures that a is always the larger or equal number, which can help reduce the number of recursive calls.

1. Recursive Case (elif (b != 0):):

• If b is not zero, the function returns a plus the product of a and b-1 (return a + product(a, b-1)). This effectively breaks down the multiplication into repeated addition.

1. Base Case (else:):

• If b is zero, the function returns 0 (return 0). This is the base case that terminates the recursion because multiplying any number by zero results in zero.

1. Input and Function Call:

• The user is prompted to enter two numbers:
  python a = int(input('Enter 1st number:')) b = int(input('Enter 2nd number:'))
• These inputs are stored in variables a and b.
• The product function is called with a and b as arguments, and the result is printed:
  python print('Product of both numbers is:', product(a, b))

Example

Let’s go through an example where the user inputs two numbers. Suppose the user inputs the following:

Enter 1st number: 3
Enter 2nd number: 4

The code execution will be as follows:

• Input Numbers:

  a = 3
  b = 4

• Initial Function Call:

  product(3, 4)

Since 3 < 4, it calls product(4, 3).

• Recursive Calls:

  product(4, 3) -> 4 + product(4, 2)
  product(4, 2) -> 4 + product(4, 1)
  product(4, 1) -> 4 + product(4, 0)
  product(4, 0) -> 0

• Unwinding the Recursion:

  product(4, 1) -> 4 + 0 = 4
  product(4, 2) -> 4 + 4 = 8
  product(4, 3) -> 4 + 8 = 12

So, the output will be:

Product of both numbers is: 12

Summary

This code defines a recursive function product that calculates the product of two numbers by repeated addition. The function ensures that the smaller number is used as the multiplier to minimize the number of recursive calls. The base case handles the multiplication by zero scenario, ensuring proper termination of the recursion.