NVIDIA Software Engineer Systems interview questions

3 phone interview, 2 technical and 1 interpersonal with the hiring manager. First phone interviews technical question was to write a binary search tree class in C, it should implement insertions, deletions and search functions. Second interview technical question was to implement a clipping algorithm in pseudo-code that could handle more clip windows than were supported in hardware. Third interview had a number of personal and moral questions. Made it to the on-site. Was asked to write my own implementation of Tail in C, was asked to write an algorithm in C that would determine if a point lay within any polygonal bounding area, and was asked to write a function that could print any UTF string in reverse. Lunch interview where I was allowed to ask question about the company, and then a personal interview with HR and the hiring manager.

maze traversal and back tracking how does a debugger work? semaphores, mutex, spin locks mutexes and spin locks in interrupts top halves and bottom halves in interrupt implement strlen function count freq of characters encoding chars into numbers for eg. abc -1 def -2 etc why padding is needed in struct difference between interrupt and exception