Factorialize a number - help understanding recursion

JavaScript
1

Tell us what’s happening:

So I’ve passed this activity and I deliberately attempted to pass it using recursion because it’s something I still am struggling to grasp. I think I understand it so far, but I’m hoping you can confirm my understanding.

First here is my code:

function factorialize(num) {
 if (num <= 0) {
   return 1;
 } else { 
 return factorialize(num - 1) * num;
 }
  
}

factorialize(5);

Now my question:

I understand that if factorialize(5) is passed in it first stores 5. Then it subtracts 1 and stores 4. Then it subtracts 1 again and stores 3 and so on. Is that correct?

Thanks,





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**Challenge:** Factorialize a Number

**Link to the challenge:**
https://www.freecodecamp.org/learn/javascript-algorithms-and-data-structures/basic-algorithm-scripting/factorialize-a-number
2

Basically that’s what happens. It needs a base case, in your case it’s num <= 0, so it does not infinite loop. Here’s a diagram to better explain:

2 Likes
3

Thank you so much. Sometimes all I need is confirmation that my understanding is correct and you provided that. :slight_smile:

1 Like