QualComm Campus Interview Experience

Qualcomm had the following four rounds of interview process

1. Aptitude + Programming MCQs + Technical MCQs
2. Tech Interview 1
3. Tech Interview 2
4. HR Round

Round 1:

It had 3 sections

1. i) General aptitude (medium level) 
2. ii) Programming MCQs : Many output based questions, object oriented concepts(interfaces, classes), pointers, operator precedence, scope and lifetime of variables, storage classes related questions.

iii) Technical MCQs: Mainly operating system, computer architecture and  data structures related questions were asked.

Note: Questions were easy and a few were tricky. The key to clear is to manage the time and mark only the questions you know (as each question had 0.25 negative marks).

Round 2: Technical Interview 1:

? He asked me to introduce myself and asked why did I leave job and took admission in M. Tech.

? He started asking the third project which I had mentioned in the resume which was related to GPU. He didn’t go in depth of the project and it looked like he just wanted to know if I recall the project :P.

? He then asked me, if I am comfortable with C++. I said yes, I’m pretty comfortable.

? He asked to explain the concept of VTable. He expected me to know where it is used and how is it implemented. I started explaining him the dynamic polymorphism through virtual function and explained how Vtable and the virtual functions are mapped and also I explained him about vptr concepts used. 

https://pabloariasal.github.io/2017/06/10/understanding-virtual-tables/

? He then asked me to write a singleton class. I explained to him the concept but he insisted me to write a class for the same. I was able to answer it by using static bool variable. Although it was not perfect, he seemed okay with the implementation.

https://www.geeksforgeeks.org/singleton-design-pattern/

? What is volatile keyword?. Explain any other compiler optimization techniques.

https://www.geeksforgeeks.org/compiler-design-code-optimization/

? Questions related to fragmentation, paging, cache memory, threads, mutex, counting semaphore, binary semaphore were asked.

? What are the disadvantages of inline functions?. I explained to him what are inline functions and I was thinking about its disadvantages but he didn’t let me think and said, thanks for your time.

https://www.geeksforgeeks.org/inline-functions-cpp/

Interview went for around 25 mins. For others it went anywhere from 25-60mins.

Round 3: Technical Interview 2

? This round was very easy for me. As I had computer architecture in resume, he asked me to explain how CPUs work. I wrote the cpu architecture diagram and explained each component. He expected me to explain instruction execution cycle in detail(stages, addressing modes etc., ). He asked if ARM uses the same pipeline stages and difference between RISC and CISC. 

? Explain the role of MMU.

? Page size in linux.

? 2D array dynamic memory allocation: https://www.geeksforgeeks.org/dynamically-allocate-2d-array-c/

? He asked two famous puzzles. 

1. i) http://www.mytechinterviews.com/apples-and-oranges

ii)https://www.geeksforgeeks.org/puzzle-18-torch-and-bridge/

Interview ended in 20-25mins. 

Round 4: HR

? Introduce yourself

? He did not ask me any further questions and started explaining about Qualcomm and its criteria. I asked questions in between to clarify many doubts I had(related to team allocation, kind of work, team preferences, location preferences, internship related etc., ). 

HR was also a filtering round, a few students who gave HR were not in the final list (Not sure about the criteria used for the final list).

Feel free to ping me for any help at https://www.linkedin.com/in/sujay-raj-728376102/