Vrbo interview question

- Algorithm for calculating fibonacci sequence, wanted recursive and iterative solution. - Data structure questions about hashmaps etc. - Fill in a 2D array with numbers in an inward spiraling pattern. - Design a system to send text messages to a texting service given certain constraints (i.e. numbers can only be used 500 times per day and send at a rate of 1 per second) - Design a system to generate/store/provide promotional unique ids for a soda company to put under their bottle caps.