How can I make this more efficient?

Question

https://code.sololearn.com/c2IFOSu81A6B/?ref=app

Answer 1

Your check for a happy number does not work because it only runs a set number of times, not until it is determined to be a happy number or not.

You should work on making your code function properly before worrying about efficiency.

Answer 2

Jackson O’Donnell That works fine. I've tested it. What do you mean exactly?

Edit: Just to be clear, the function runs until it reaches one, or it catches up to itself. Not a set number of times. Where did you get that from?

Answer 3

I'm sorry, I didn't see the loop.

A way to make it more efficient would be to make an array w/ all the digits squared and pull from that rather than using multiplication.

int digSquares = [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]

Then sum += digSquares[x%10];

You can also save known digit-sum pairs in a map and look through that for the sum first, but this will onky work with very large numbers