Can anyone tell me how to optimise this code ?

Question

https://code.sololearn.com/cimbVk21Hg1U/?ref=app

Answer 1

Shorter

Answer 2

Denise Roßberg In number theory, a happy number is a number which eventually reaches 1 when replaced by the sum of the square of each digit.

Source: https://en.m.wikipedia.org/wiki/Happy_number

I once tried to create some codes of such sequences, thus I found this. 🙂

Answer 3

Denise Roßberg do normal methods decrease time complexity or the inbuilt methods?

Answer 4

Anyone please answer?

Answer 5

Optimise for what? Do you want it to be faster or shorter?

Answer 6

Denise Roßberg you have too created this number
Genuine Stalwart thanks for sharing the information beforehand

Answer 7

Atul this? 🤔

https://code.sololearn.com/c4am0UYC9tnC/?ref=app
https://www.sololearn.com/learn/4539/?ref=app

Answer 8

Atul Genuine Stalwart
1 year ago! Feels like ages for me. lol

But I would say my isHappy() method is fine.
Maybe there would be also a way to solve it with streams but I don't think that you can do it shorter.

Answer 9

Genuine Stalwart yes

Answer 10

And I don't want to use do while loop in this process

Answer 11

7 is a happy number

Answer 12

Denise Roßberg I have not learnt about streams but I can take one idea of that if condition. Thanks

Answer 13

Atul

Can you explain what a happy number is?

Answer 14

I tried a stream solution:

https://code.sololearn.com/c43ICk4WPJ0Q/?ref=app

A bit shorter but the code does not check the input.

Answer 15

Atul Thanks. Now it works.

Answer 16

Here you find more about streams:

https://www.baeldung.com/java-8-streams
(String.chars() returns an IntStream.)

Conclusion: using inbuilt methods can shorten your code but not always. ;)

Answer 17

I would say it depends on your code or the problem you want to solve.

But I think inbuilt methods do for what they are built for in an effective way. And they can simplify your code. You don't need to write an own method if you already have an inbuilt method which does the same.