Candidate Information:
- Status: Final-year M.E. Computer Science student, selected for Software Engineer role at Qualcomm
- Relevant Experience: Fresher / 0 years of professional experience
- Target Position: Software Engineer
- Company: Qualcomm
- Location: BITS Pilani, K.K. Birla Goa Campus, Goa, India
- Interview Type: On-campus placement
- Interview Date: August 3, 2026
Overview of Interview Process:
The Qualcomm on-campus selection process I experienced consisted of four stages:
- Technical Round 1
- Written Technical/Coding Test
- Technical Round 2
- HR Round
The interviews were particularly focused on C programming, Operating Systems, Kernel/System concepts, pointers, bit manipulation, linked lists, and basic problem-solving.
Since the interview panel was from an embedded/systems-oriented team, there was significant emphasis on low-level programming and understanding how systems work internally.
Technical Round 1
Duration : Approximately 45–60 minutes.
Method : In-person interview.
Focus : The first technical round primarily focused on:
- C programming
- Pointers
- Operating Systems
- Kernel concepts
- System calls
- Basic Dynamic Programming
- Logical reasoning and puzzles
Key Questions
1. C Pointers
The interviewer started with a few questions based on pointers in C.
The discussion involved understanding pointers, memory, pointer operations, and how data is represented and accessed in memory.
This made it clear that strong C fundamentals are very important for Qualcomm's systems/embedded-oriented roles.
2. 9-Ball Puzzle
I was given the classic 9-ball weighing puzzle. There are nine balls, one of which has a different weight. However, we don't know whether the odd ball is heavier or lighter. The task was to determine the odd ball and whether it is heavier or lighter using the minimum number of weighings.
The interviewer was interested in my approach and reasoning rather than simply getting an answer immediately.
3. System Calls and Kernel
Since I had a project related to system calls, the interviewer went deeper into this area.
Some of the discussion included:
- What is a system call?
- Why are system calls required?
- How does a system call work?
- What happens when a user program invokes a system call?
- User mode vs. kernel mode
- How control moves from user space to the kernel
- How the kernel handles the request
- How execution eventually returns to the user program
This was one of the most important parts of the round.
Important lesson:
If you mention a project on your resume, be prepared to explain it in depth.
It is not enough to know what you implemented. You should understand the underlying concepts, design decisions, execution flow, and possible follow-up questions.
4. Climbing Stairs — Dynamic Programming
I was given a basic DP problem:
There are 10 stairs and we start at stair 0. At every move, we can climb either 1 or 2 stairs.
The question was to find the number of ways to reach the 10th stair.
- The recurrence is:
- ways(n) = ways(n-1) + ways(n-2)
The discussion focused on the problem-solving approach and the underlying DP idea.
5. Water Jug Puzzle
Another puzzle involved jugs of different capacities, including a 5-liter jug and a 3-liter jug.
The task was to obtain exactly 4 liters in the 5-liter jug using the minimum number of operations.
This was another problem designed to test logical thinking and the ability to systematically explore possible states.
Obstacles / Difficult Moments
The main challenge was that the interviewer frequently moved from a basic question into deeper follow-up questions.
For example, a question about a system call could lead into kernel mode, execution flow, and how the operating system handles the request.
Therefore, I would recommend preparing concepts deeply rather than memorizing isolated definitions.
Written Technical Test
After the first technical round, I was given a written test.
Focus :
The test consisted mainly of C++ code snippets involving classes, threads, and language-level concepts.
There were approximately five code snippets.
For each snippet, I had to:
- Identify the line containing the error
- Explain why the error occurs
- Correct the error
The questions tested whether I could understand the code and reason about the language rules rather than simply identify syntax mistakes.
Topics included concepts such as:
- Classes
- Constructors
- Object initialization
- const members
- C++ semantics
- Threads
- Compilation errors
- DSA Question
The final part included a DSA/coding question.
I had to write a C function to reverse the words in a sentence in-place.
For example:
Input:
hello world from qualcomm
Output:
qualcomm from world hello
The important constraints were:
- Reverse the order of words
- Do it in-place
- No extra space
- Only one space between words
This tested string manipulation as well as understanding of memory and C programming.
Technical Round 2
The second technical round focused more heavily on DSA, bit manipulation, interrupts, and low-level/system concepts.
Focus
The major areas were:
- Linked Lists
- Bit Manipulation
- Endianness
- Interrupts
- Interrupt Service Routines
- Low-level system concepts
1. Linked List
I was asked several linked-list questions.
Detect a Loop:
How can we detect whether a linked list contains a cycle?
The standard solution is Floyd's Cycle Detection Algorithm, using slow and fast pointers.
Delete a Loop:
After detecting a cycle, I was asked how to remove it from the linked list.
Duplicates in Linked List:
I was also asked about finding duplicates in a linked list and the possible approaches depending on the constraints.
The interviewer was interested in both the solution and the associated time and space complexity.
2. Bit Manipulation
I was asked several basic bit-manipulation questions.
For example:
Set the ith Bit
n = n | (1 << i);
Check the ith Bit
if (n & (1 << i))
Clear the ith Bit
n = n & ~(1 << i);
Toggle the ith Bit
n = n ^ (1 << i);
These are simple operations, but they are important for embedded and systems-oriented roles.
3. Endianness
I was asked how to determine whether a system is little-endian or big-endian using low-level programming/bit manipulation.
One common approach is to inspect the first byte of a multi-byte integer:
int x = 1;
char *p = (char *)&x;
if (*p == 1)
printf("Little Endian");
else
printf("Big Endian");
The important concept is understanding how multi-byte values are stored in memory.
4. Interrupts
The interviewer went relatively deep into interrupts.
The discussion included:
- What is an interrupt?
- Hardware vs. software interrupts
- Interrupt Service Routine (ISR)
- How an ISR is executed
- Interrupt flags
- Interrupt handling
- What happens when an interrupt occurs
- How the processor handles the interrupted execution
For an embedded/systems role, I would strongly recommend understanding interrupts beyond just their definition.
You should be able to explain the general flow:
Hardware Event
↓
Interrupt Generated
↓
CPU Detects Interrupt
↓
Current Execution State Handled
↓
ISR Executed
↓
ISR Completes
↓
Previous Execution Resumes
HR Round
The final round was an HR interview and was comparatively straightforward.
The discussion included:
- Tell me about yourself
- Background and general introduction
- Questions about relocation
- General HR/conversational questions
There were no particularly unexpected questions in my case.
The main thing is to remain confident and consistent with what you have already discussed in the technical rounds and what is written on your resume.
Post-Interview Reflections:
- Company Culture Insights : Since my interaction with Qualcomm was primarily through the recruitment and interview process, I don't think it would be appropriate to make broad claims about the company's internal culture based only on the interviews. However, from my interview experience, the technical evaluation appeared to place a strong emphasis on fundamentals, problem-solving ability, and low-level understanding.
- Work Environment : The interview was conducted as part of the on-campus placement process at BITS Pilani, Goa Campus. The interview environment was professional, with the technical discussions being largely focused on understanding my fundamentals and reasoning process.
Evaluator Feedback / Interviewer Interaction:
One interesting aspect of the technical interviews was that the interviewers sometimes challenged my answers or asked follow-up questions even when I was confident in my response. This is something future candidates should be prepared for.
If you are confident about an answer:
- Think through it once again.
- Explain your reasoning clearly.
- Don't change your answer merely because the interviewer challenges you.
- If you discover that you are wrong, acknowledge it and correct yourself.
- If your reasoning is sound, defend your answer politely.
The goal is not to argue with the interviewer. The goal is to demonstrate clear technical reasoning and confidence.
Closing Note:
Overall, my Qualcomm interview was a very good learning experience. The process made it clear that for systems and embedded-oriented Software Engineering roles, strong fundamentals in C, Operating Systems, kernel concepts, memory, and low-level programming can make a significant difference.
I hope this experience helps students preparing for Qualcomm, especially those targeting Software Engineer, Embedded Software, Firmware, Systems, or other low-level roles.
All the best to everyone preparing for their placements!
