Qualcomm Interview Experience | (Pool Campus Drive)
Around 30 students attended the Round 1 (B.Tech + M.tech of my college)
Round 1: Online Test
It has 3 sections. Each section has 20 questions with +1 for correct answer and – 0.25 for wrong answer.
Section I: (Aptitude)
Questions were from following areas/topics:
1. Works and wages
2. Time and distance
3. Pie chart
4. Data Interpretation
There were some 1-2 other topics also.
Section II: (Programming- C based objective)
Questions were based on the following topics:
1. Pointers and typecasting of them.
2. Operators precedence and associativity
4. Static variable
6. Reference variable
Section III: Technical (Branch wise questions)
For me, I opted Computer Science option according to my branch.
Questions were to test one’s technical knowledge of CS Subjects (Gate level questions)
1. OS based questions ( Threads, synchronization)
2. C / C++ based questions
3. Computer Architecture based
2-3 more topic questions.
Each section was of 30 minutes. After 30 minutes, the timer expires for that section and next section comes.(You cannot switch between sections and cannot go back to previous section even ), so manage your time wisely. Attempt as much questions as you can taking care of negative marking.
After Round 1, 7 students were selected for further rounds.
For all further round, they called all 7 students of my college for further interviews to their Hyderabad office. Qualcomm made all travel arrangements/expenses for attending the interviews .
Round 2: Technical ( 1:1 interview) – 50 min.
It was a pool campus drive for Full time employment (Batch 2019 B.Tech / M.Tech). Students from 3 colleges were called at Qualcomm office (Hyderabad): IIIT Delhi, Nirma University and Lovely Professional University.
Around 40 students were called.
1. Tell me about yourself
2. Rate yourself in OS.
3. What do you know in OS.
4. What is process, thread? Difference Between process and thread.
5. What resources does a process use?How does the process
resources information is maintained?https://www.geeksforgeeks.org/operating-system-process-table-process-control-block-pcb/
6. What resources do threads use?https://www.geeksforgeeks.org/operarting-system-thread/
7. What should we do if we do not want to share a file among threads?
8. What are locks?https://www.geeksforgeeks.org/lock-variable-synchronization-mechanism/
9. What is mutex ?What is semaphore? Difference between them.
10.Mutex vs Binary semaphore? Are they logically equivalent ?https://stackoverflow.com/questions/62814/difference-between-binary-semaphore-and-mutex
11.What is virtual memory and why do we use it?https://www.geeksforgeeks.org/virtual-memory-operating-systems/
12.What is demand paging? How to map logical to physical address?https://www.geeksforgeeks.org/virtual-memory-operating-systems/
13.Which address is known to CPU?
14.What is volatile keyword? Why do we need it?https://www.geeksforgeeks.org/understanding-volatile-qualifier-c-set-1-introduction/https://www.geeksforgeeks.org/understanding-volatile-qualifier-in-c/
15.What is static variable ?Show by example.https://www.geeksforgeeks.org/static-variables-in-c/
16.Where does static variable get stored?https://www.geeksforgeeks.org/memory-layout-of-c-program/
17.What is static function?
18.What is Dangling pointer?
19.What is memory leak? Give example by code. In what scenario
memory leak is critical and problematic? https://www.geeksforgeeks.org/what-is-memory-leak-how-can-we-avoid/
It is critical where the system reboot is infrequent and are very costly
affair . Example: servers
20.Rate yourself in C
21.Set ith bit of a number ? Input is the number and position . Check all
invalid input cases. Set the K-th bit of a given number
Invalid cases like inputting wrong position.
22.Reset ith bit of the numberhttps://stackoverflow.com/questions/47981/how-do-you-set-clear-and-toggle-a-single-bit
Round 3: Technical ( 1:1 interview) – 40 min
3. Memory map of the process.https://www.geeksforgeeks.org/memory-layout-of-c-program/
4. Tell me about process scheduling algorithms?What is round robin algorithm?https://www.geeksforgeeks.org/gate-notes-operating-system-process-scheduling/
5. Spinlocks vs mutex vs semaphorehttps://practice.geeksforgeeks.org/problems/explain-spin-lock
6. Tell about bitwise operators. Asked some questions on it.https://www.geeksforgeeks.org/bitwise-operators-in-c-cpp/
7. Print odd number by one thread and even no by other.How u will
implement it ?
I told him using semaphores, wait() and signal()
8. C programming output question: Based on various type of pointer typecasting.
9. C programming output question: Based on local vs global variable precedence.
10. What is priority Inversion? https://www.geeksforgeeks.org/priority-inversion-what-the-heck/
11. Structure padding and packing. Who do this padding and packing( compiler, cpu etc.)?
12. Internship work discussion
13. Why did you do the teaching for 5 years and then did M.Tech? ( I taught to Undergraduate students in GEHU, Dehradun for 5 years)
14. Then Interviewer asked do you have any questions for me?
I asked about his work and his team at Qualcomm .
Round 4: HR interview -20 min
1. When did you arrive at office?
2. Didn’t you attended the Qualcomm drive when we came to your college
for your batch?
3. Why reason do you think that you were not able to qualify Online test at that time and you qualify this time?
4. Do you like the work which the interviewer has discussed with you?
5. Reasons for doing Teaching Job for 5 years?
6. Discussion about family
7. Discussion about relocation.
After 2 days, result came to Placement office and I was selected .
Feel free to ping me for any help at www.linkedin.com/in/dilip-kumar-gangwar