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Recursion vs. Iteration - Coding Throwdown

Multiplication? Schmultiplication!

All programming languages you’re likely to use will include arithmetic operators like `+`

, `-`

, and `*`

.

Let’s pretend Python left out the multiplication, `*`

, operator.

How could we implement it ourselves? Well, multiplication is repeated addition. We can use a loop!

Here’s an iterative approach:

def multiplication(num_1, num_2): result = 0 for count in range(0, num_2): result += num_1 return result multiplication(3, 7) # 21 multiplication(5, 5) # 25 multiplication(0, 4) # 0

This implementation isn’t quite as robust as the built-in operator. It won’t work with negative numbers, for example. We don’t expect your implementation to handle negative numbers either!

What is the big O runtime of our implementation?

### Instructions

**1.**

Implement your version of `multiplication()`

which has the same functionality **using recursive calls!**