I am making a post about these usual programming trick questions and give out their solutions because, I really want to show you how simple it could be and advise you that you do not “overthink” it. Oh, I am not giving you exactly in a programming code, but maybe just something like a pseudo-code.
If you have other trick questions that you might want to share, please post it as a comment.

Problems:

1. ) How do you swap two integer values from two variables without using another variable?

2. ) How do you convert an integer ranging from 0 to 999,999,999 to words?

Solutions:

1.

a = a + b;
b= a – b ;
a = a – b ;

2. Note: You’ll have to do this in divisions(functions) to parse a number and convert it to to words. And In each division you have to know if they are in the millions, thousands and ones. (Another Note: I heard from someone that this type of trick question may have a slight variation like, giving out their conversion to Roman Numerals.)

I also tried this in PHP, and you can try the live demo

If(num >=1000000 && num1000 && num1 && num