After you see the algo you will think, wow that was quite easy :D

I honestly don't recall if that has been the case, sorry.
When I saw the procided solutions from other users I also
realized that it didn't matter what the input number was
but I just felt it wasn't very well stated in the description.
So I got a bit confused.

wow, i didn't expect that way of solve it... i guess i should improve with algorithms

Java Translate is ready, please cheack it :D

Now do it without loop, in O(1) ;)

It should be 7/8 kyu, but it was funny to solve it

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Oh, sorry. I've just added it, tell me if i did something wrong plz

No random tests, no one approve it.

That is wrong.

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https://www.codewars.com/kumite/5f3bf591d0e11a00106f4f52?sel=5f3bf591d0e11a00106f4f52

Thanks you :D. It clarifies more things to me, to be honest... xD

That's because how type promotions work in C.

This will not work: long toRet = firstNumber + secondNumber because result of addition of two ints is also an int, so addition overflows, and then such overflowed result is assigned to toRet. Addition result is not extended to long until actual assignment.

However, these two will work:

long toRet = (long)firstNumber + secondNumber, and

return (long)firstNumber + secondNumber

They work because you explicitly promote one of operands to long, so actual addition is performed with longs and does not overflow.

Main difference is: in the first case, you work with ints and you add two ints, receiving int in the result. In two remaining cases, you cast one operand to long, the other gets implicitly promoted to long, so you perform addition on two longs.