Google Interview Question

In the phone call the engineer asked me two programming questions: Implement a function that calculates in how many ways it is possible to climb a stair given that you can raise one step or two step at a time. (solution Fibonacci like) Then asked me general info about fibonacci sequence and few questions in the field of algebra (modulo operations). Second problem was to generate a random sequence of number for Lotto extraction. Onsite i had three interviews: 3 about programming and 1 about system design (general question about detecting bot in social network, youtube and google+).