All programming languages you’re likely to use will include arithmetic operators like
Let’s pretend Python left out the multiplication,
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?
Implement your version of
multiplication() which has the same functionality using recursive calls!