"Software developers design, write, test, and maintain the code for a software system. Extensive knowledge of programming languages, data structures, and algorithms are necessary to pass the technical interview which is designed to test these skills. Employers are looking for candidates with a bachelor's degree in computer science or related field or equivalent work experience. "
How many gas stations are in this city?
There's no specific answer they're looking for - it's just a way to see if you are creative under pressure.