It was a very good experience to face interview at Qualcomm (Hyderabad-2016)
I have attended the interview for a position of Software Engineer and My experience and Questions are mentioned below.
Round-1 Telephonic around (40min to 1hr) Medium level.
- All about your CV
- Lots of questions on project and how it works actually
- OS concepts and real examples
- Deadlock situations (detection ,prevention)
- Sw watchdog timers
- OS schedulers and algos
- Error handling in the system , Core dumps ,etc
- Memory management concepts
- Mutex/critical section/semaphores
- Dsp processor, pipeline, and serial IC
- 3 Coding questions (LinkedList, stack based, and string based).
Note: All round questions were asked deeply and need to tell him until he convinced with the answers. After 7 days I got a call to come down to Qcom office for next rounds. That day went from 10 to 4 clock break only for lunch.
Round 1 (2 person took from 10 to 12.30):
- Started with my resume, asked questions on my internship projects, main projects.
- Basics of C programming.
- 5 coding questions (bit wise, Fibonacci, LinkedList, trees, and pattern recognition)
- Then started with os concepts, scheduling algorithms, best data structure for real time scheduling.
Memory map of program, Storage classes and their mapping - If we declare more number of variables than the registers available on the processor? Where they will be stored.
- IPC (signal, as I coded in this) how actually it does transfer of memory
- Set of C code snippets given to debug … Identify problems in it and tell outputs
- Memory questions like Best fit, worst fit, average fit questions.
And further questions on that.. like why?
Round 2 (coding):
- Basic C questions and resume questions
- Write a program to Delete a node, given only a pointer to the node in a Circular linked list
- How to access data in the called functions after returning from it (point here is that, cannot access auto variables in functions after it is being called off )
- Write a program to return a stream of bytes from a function
- Lots of questions on Function pointers, how, usage, examples
- There was an IPL tournament, after every match you have to find the team with max points. You have to tell logic first then code it.
- LinkedList questions print every odd node first followed by even node without changing the LinkedList.
Round 3 (coding):
- Generic questions on project they are doing, how market values are there, what products are coming
- Count the occurrence of pattern 011110 in a large binary file.
- Questions on semaphores and mutex
- Questions on Call back functions
- Questions on function pointers
- Program to Reverse a single linked list
- Program to Detect loop in a single linked list
- Priorities of OS programs, process and thread differences
- How to handle the Generic functions, like Void pointers
- Similar coding question level order spiral form.
- Find the Next Permutation number.
- Retrieve the max 6 file in a folder who’s size greater than 1MB.
Round 4:
- Write a own program for strstr function, optimal way
- Write a program to convert a given single Linked list to BST
- Questions on macros
How do you want to see yourself after a year, you intentions, aspirations
Big & Little endian – definitions, representations, write it down, swap them, etc - Lots of memory related questions
- Write a program to implement memcpy() on your own
- Need to evaluate many other conditions like overlap situations and etc.,
- Difference between library call and a system call
- Priority inversion in a RTOS and its solutions
Round 5 (Manager):
Qualcomm aspirations, culture and how you look to be next, feedback from us on the interview, Nothing much… just a casual talk.
Round 5 (Hr):
Why Qualcomm? Relocation? salary expectation? just a casual talk.
Note: All rounds, you need to explain about your project clearly and they can ask some really good questions from your project. Be out and out clear with your projects and CV.
After this, I was actually into my Dream Company and Happy..!!
I suggest that always listen carefully to an interviewer, they’ll definitely help if you have any doubt. Tell them your approach at least if you are not able to code it. Practice writing code on paper. For Qualcomm Arrays, Linked Lists, Strings and Trees are concepts which are very generally asked. Data structures & algorithms, OS should be proficiently practiced.
I would sincerely Thank GeeksforGeeks very helpful in my preparation and hope this would be useful for other aspirants.