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R1 (F2F) (Virtual)
1 - You can climb either(1,2,3) stairs at once, total number of ways to climb N stairs.
2 - Same question with a variation(if at any point you have taken x steps, you cannot take less than x steps again, eg. 1,1,2 will be an answer but 1,2,1 won't be, eventually you have to provide all unique ways)

Java

1. Difference between abstract class and interface
2. What all access specifiers are used in interface?
3. There is a class with final static variable and it is not initialised yet, will it compile? If not how will you fix it?
4. Different methods to create thread?
5. How do we start a thread, what happens when run is called instead of start, which method start calls internally?
6. Have you used any message queue?
7. What type of databases have you worked on?