How can I calculate Fibonacci numbers iteratively?

Can you explain how to calculate Fibonacci numbers using an iterative approach?

Sure! The Fibonacci sequence is a series where each number is the sum of the two preceding ones. In an iterative approach, you can use a loop to calculate the numbers.

What would the code look like in Python?

Here's a simple Python code snippet:

def fibonacci(n):
    a, b = 0, 1
    for _ in range(n):
        a, b = b, a + b
    return a

How does this code work step by step?

The code initializes two variables, a and b, to 0 and 1. It then iterates n times, updating a and b to the next Fibonacci numbers in each iteration.

Can this method be optimized further?

Yes, you can optimize it by using memoization or even matrix exponentiation for larger values of n.