Qualcomm Interview Experience (On-Campus)

Qualcomm visited our campus in July 2022 for Software Engineer Role

Written Round: This round is MCQ based round and is divided into 3 sections:

• Aptitude: This section mainly consists of questions like speed and distance, data interpretation, ratio, and proportion. The level of questions was medium but was time taking so plan your time accordingly.
• C Programming: This section consists of questions based on C programming. Most questions were based on finding the output and some were based on finding the errors. output-based questions mainly focused upon logical operations like XOR, AND, and OR operations. These questions were of easy level but require accuracy for solving logical operation questions.
• Technical: This section focuses on core CS concepts like OS, CN, and DBMS. It also had questions on quick sort, merge sort like what is the pivot in 2nd iteration, etc. Questions on OOPs were also asked. Most of the questions were of medium level and some were of easy level.

Each question carries 1 mark for a correct answer and -0.25 for every incorrect answer. There is a sectional cutoff which you have to clear. It will be cleared in your pre-placement talk.

Technical Interview 1: This round started with questions on C programming like the difference between structure and union, and structure padding https://www.geeksforgeeks.org/structure-member-alignment-padding-and-data-packing/ His next question was based on differences between array and linked list. He wanted to know the concept of addition, deletion, and time complexity of accessing certain data. After that, he asked me questions on dynamic memory allocation- the difference between calloc and malloc https://www.geeksforgeeks.org/difference-between-malloc-and-calloc-with-examples/

After that, he switched to coding questions. Following coding questions were asked:

• Implement a linked list with employee details and add data of 6 employees in the linked list.
• Implement a singly linked list. You can read it from https://www.geeksforgeeks.org/linked-list-set-1-introduction/
• Write a program for the testing ASCII value use of the given integer. https://www.geeksforgeeks.org/program-to-print-ascii-value-of-all-digits-of-a-given-number/ He asked me to return the answer in a char array.
• Write a program to find whether a number is a power of 4 or not. https://www.geeksforgeeks.org/find-whether-a-given-number-is-a-power-of-4-or-not/ He expected an optimized solution.

All the questions were to be coded on Notepad. This concluded my round 1. I was able to answer almost all questions except the first coding question. The interviewer was very helpful and was continuously trying to take me in to correct direction in case I was going out of my way.

Technical Interview 2: This round started with an explanation of my project. He expected me to explain the motivation of the project, how it is different from the existing product in the market and what I can add in the future to it.

Then he started with Operating System. First, he asked about paging https://www.geeksforgeeks.org/paging-in-operating-system/ I explained to him contiguous, non-contiguous memory allocation, address conversion, page table, and its memory requirements.

Next, he asked the question about segmentation v/s paging (https://www.geeksforgeeks.org/difference-between-paging-and-segmentation/).

After that he asked me about page fault and after explanation, he presented a scenario that what is the problem if only one process is there in main memory and all pages are present in main memory. Initially, I explained the possibility of a thrashing if one more process is brought into the memory and the initial process is still executing. Then he ruled out the possibility of getting another process and said the process is very large. I answered it by relating the concept to increased page table size and he was expecting that only.

Next question was to differentiate between process and thread. I explained all the major differences and also about multithreading and multiprocessing as well as context switching in both threads and processes. https://www.geeksforgeeks.org/difference-between-process-and-thread/

Next, he asked me about spooling https://www.geeksforgeeks.org/what-exactly-spooling-is-all-about/

After that, he switched to Computer Networks. The questions asked were:

• Three-way handshaking https://www.geeksforgeeks.org/tcp-3-way-handshake-process/
• Closing a TCP connection https://www.geeksforgeeks.org/tcp-connection-termination/
• Flow and Congestion control in TCP https://www.baeldung.com/cs/tcp-flow-control-vs-congestion-control
• Difference between TCP and UDP https://www.geeksforgeeks.org/differences-between-tcp-and-udp/
• Give a real-life example for explaining the difference between TCP and UDP which can be easily understood by a person unaware of any technical concepts.

In the end, he asked me a coding question: https://www.geeksforgeeks.org/merge-two-sorted-linked-lists/ First I explained to him the logic, and then he asked me to code it on the gfg practice portal itself.

Verdict: Selected