Pregunta de entrevista de Nexmo

#1. Write a linked list class and a find a node in it function and a find if there's circular dependency function. #2.Missing integer in an array consisting of numbers from 1..100, having the size 99. #3. How permutations of one and two steps there are for climbing a N staircases, where each staircase is one bigger than the previous, i.e. first stair has a size 1, second a size 2, third size 3. For instance to get to 3rd stair it takes two permutations, 4th takes 3, the 5th takes 5 and so on. The answer is the Fibonacci series. #4. How to reverse a string in place. #5. Difference between heap and cache. #6. How to check in a Map using java.util.concurrent if an ID (the key in this case) is there and notify other threads about it so that if they search for that ID at the same time they can see it. #7. Write a set_timer2() function using a set_timer() using only a data structure of your choice and without the help of extra threads. For full details go to explanation written at the "Describe the Interview Process". #8. Explain the system design of one of your previous projects.