Interview Process:

• Online Coding Test (Hackerrank)
• Onsite Interview:
  • Three rounds of Technical Discussion
• HR Round

On the immediate day of submission of the online HackerRank test, I received a call and an email confirming the onsite interview date and time for the QC, Hyderabad office. They also sent a form to be filled out for accommodation and travel arrangements. Qualcomm arranged (cabs, flight tickets, hotel room, and food) from the time I left home to the time I returned.

QC offices in Hyderabad are distributed across five different buildings. My interview was scheduled at Building No. 6.

Since I am a fresher, for the first two rounds, they did not discuss anything from my resume and just tried to check the skill sets required for the job profile. In the third technical discussion, they asked questions from my resume and projects.

Finally, they asked me to leave, saying that they would most likely be moving forward with me and the pending HR round would be held via phone call or perhaps just an email.

After one week, I received an email seeking my responses to some HR questions. I submitted the responses the very next day.

After three weeks, I got the offer letter.

Online Coding Test (1.5 hour): Lang: C/C++

Problem 1: Given a singly linked list of integer values. You must remove all values greater than a given integer N, maintaining the integrity and order of the list. From this function, you need to return a pointer to the head of the updated list.

Problem 2: Given an array of integers. Your task is to find the number of duplicate elements. A duplicate is defined as two or more identical elements. For example, in the array [1,2,2,3,3,3], the two twos represent one duplicate, and the three threes represent another. The number of duplicates is 2.

Problem 3: Write a function to add two floating-point numbers. Determine the integer floor of the sum. The floor is the truncated float value, i.e., anything after the decimal point is dropped. For instance, floor(1.1 + 3.05) = floor(4.15) = 4.

Problem 4: Find the number of "distinct" pairs in an array whose sum is equal to a given number.

1st Technical Round (around 2 hours)

OS Based Questions:

• What is an operating system?

• What services does an operating system provide?

• What are different scheduling algorithms?

• What are synchronization techniques?

• Difference between Mutex and Semaphores?

• What is a Deadlock?

• What is fragmentation in OS?

• What are pages in memory management?

• What is an Interrupt?

• Given three processes A, B, C with 1, 2, 3 priority values respectively. Which one will run first, and what will happen if a new process of higher priority is added afterward?

• How does cache memory work?

• A few questions about embedded protocols.

• In-depth discussion about some Linux tools.

C and OOPS Based Questions:

• What are Storage Classes and their use?
• What is Polymorphism?
• Write a program to remove elements from a Linked List.
• Write a program to arrange elements of a doubly linked list such that the updated LL has data of even indexes at the beginning, followed by data of odd indexes. I.e., Given Linked List: {A → B → C → D → E → F…}, the output should be {A → C → E → B → D → F…}.

2nd Technical Round (around 2 hours)

1. Write a program to find if a linked list is circular or not.
2. What is a function pointer? What is the data type of a function pointer? How to define it in C?
3. Given two binary numbers A and B. Write a program to find how many binary bits of ‘A’ need to be flipped in order to get number ‘B’.
4. Write a program to find the number of ‘1’s in the binary representation of a number.
5. What is the ‘virtual’ keyword used for?
6. What is the ‘static’ keyword in C?
7. What is the need for synchronization mechanisms such as Semaphore and Mutex? And why do we need OS support for implementing these two?
8. Given a singly linked list. You don’t have a reference to the head pointer. Given a node address that needs to be deleted from the LL. Write a program to implement the same.
9. Write a strMove() function in C. Given the prototype of the function as “void strMove(char* sourceAdd, char* destinationAdd);”, how will you implement cases where overlapping is happening?

3rd Technical Round (around 2 Hours)

1. In which projects did you use C programming?
2. About College? (since my college was unknown to them)
3. About family background?
4. About your accomplishments.
5. Discussion about various training you attended.
6. Different subjects that you studied during your 4 years at college?
7. They explained the kind of projects their teams are doing at Qualcomm and asked if you are interested in them.
8. They asked about other offers you already have.
9. What are your future plans?