Perhaps the answer to my question will end up being: “Both are valid lines of code.”
… but I’ve been starting out and its been a little difficult thinking through my own problems without looking at the solution.
The task is part of the loops exercises in Ruby and I need to find the factorial. As I learned factorials counting down (ie - 3! = 321) I started thinking using the “-=” operation. After giving it some thinking I came up with:
product = 1
- while num > 0*
- product = num
- return product*
puts factorial(3) # => 6, because 1 * 2 * 3 = 6
puts factorial(5) # => 120, because 1 * 2 * 3 * 4 * 5 = 120
After having it produce the correct results, I excitedly turned to the solutions page to see that it was not the same:
product = 1*
i = 2*
while i <= num*
product = i
i += 1*
Is there a reason why they used i+=1 instead of counting down like I did? Is it to avoid a common error that I might get in the future?