Qualcomm interview experience Real time questions & tips from candidates to crack your interview

Associate Engineer

Qualcomm

3 rounds | 11 Coding problems

Anonymous

Fresher | Jul 2022

Rejected

Interview preparation journey

Journey

Basically, I completed my M.Tech at IIIT-Delhi. The programming culture there is so great that I started practicing programming in my first year. I have started with basic data structures and gradually increase the difficulty of various problems. In addition, I practiced a lot on different programming platforms and participated in programming competitions on different platforms. So this way I built up the confidence and prepared well for the placement.

Application story

I've applied through On Campus Placement at my college IIIT Delhi. Basically the first round was Online Assessment and got the shortlisting list next day. After that they have conducted Interview process and It was 3 round in one day only. So keep yourself ready for whole day if you have same case as me.

Why selected/rejected for the role?

Actually, I did my best during the interview. However, at some point I feel that my answers did not satisfy the interviewer.I believe that was the reason for my rejection. I was a little nervous because all the round is going to be in one day. Therefore, before going to the interview, it is recommended to get a good rest, not to think about the result and perform well.

Preparation

Duration: 4 months

Topics: OOPS, Data Structures, Algorithms, Dynamic Programming, Technical Subjects - Operating System, Computer Network, Database Management System, Programming & Data Structure, Aptitude, Puzzles

Tip

Tip 1 : Prepared well for how to approach the solution of problem.
Tip 2 : Start with bruit-force approach and gradually optimize further.

Application process

Where: Campus

Eligibility: 6.5 CGPA

Resume tip

Tip 1: Whatever you write in resume, make sure you are enough confident and ready to explain it in a detail.
Tip 2: Keep your resume as simple as possible. Don't go with highly designed format.

Interview rounds

Round

Medium

Online Coding Interview

Duration90 minutes

Interview date10 Jul 2022

Coding problem3

It was in the evening 08:00 PM. Environment was quite good and no any additional disturbance was there. Internet connectivity was also decent and I was very confident about this round.

1. OS Question

Job Scheduling Algorithm were asked to solve and find the correct answer from the options.

Problem approach

Tip 1: Practice a lot of job scheduling algorithm based question.
Tip 2: Also look at the advantages of various job scheduling algorithm as there can be many theoretical MCQs
asked in Online Assessment.

2. What will be the output of the following code snippet?

#include union School {

int age, rollNo; double marks;};void solve() { union School sc; sc.age = 19; sc.rollNo = 82; sc.marks = 19.04; printf("%d", (int)sizeof(sc));}int main() { solve(); return 0;}

Problem approach

Debug the code and find the output.

The size of a Union is equal to the size of the largest variable which is a part of it. Here the variable is double which of size 8bytes.

3. What will be the output of the following code snippet?

#include

void solve() {

char s[] = "Hello"; printf("%s ", s); char t[40]; strcpy(t, s); printf("%s", t);}

int main() { solve(); return 0;}

Problem approach

The strcpy() is a string library function of C, which copies the contents of one string into another string.

Ans: Hello Hello

Round

Medium

Video Call

Duration55 minutes

Interview date12 Jul 2022

Coding problem5

- Interviewer was good and quite friendly. Interviewer has asked to Introduce myself.
- He asked me about Operating system questions.
-What is mutex?
- Difference between mutex and semaphores.
- How do deadlocks occur and how do prevent deadlocks?
- What is virtual memory and how it is achieved?
- What is the advantage of using thread over process?
- Then Interview jumped to OOPS concepts.
- What is Inheritance and Constructer.

1. OOPS

Implement Runtime Polymorphism with Multilevel Inheritance

Problem approach

class Animal{
void eat(){System.out.println("eating");}
}
class Dog extends Animal{
void eat(){System.out.println("eating fruits");}
}
class BabyDog extends Dog{
void eat(){System.out.println("drinking milk");}
public static void main(String args[]){
Animal a1,a2,a3;
a1=new Animal();
a2=new Dog();
a3=new BabyDog();
a1.eat();
a2.eat();
a3.eat();
}
}

2. Flip given bits

Easy

15m average time

80% success

0/40

Asked in companies

You have been given an integer 'NUM' (32 bits) and an array of size 'N'.

Your task is to flip all the bits of 'NUM' at position 'ARR[i]' where 0<= i <= N-1.

Try solving now

3. OS Question

Difference between mutex and semaphores

4. OS Question

How do deadlocks occur and how do prevent deadlocks?

5. OS Questions

What is the advantage of using thread over process?

What is mutex?

Round

Medium

Video Call

Duration50 minutes

Interview date12 Jul 2022

Coding problem3

It was a Technical + Managerial kind of round.
- Interviewer told me to introduce myself first.
- Started asking question based on my resume.
- Explain all the projects in detail
- OS questions like what is Segmentation, tell me the memory management techniques
- Some puzzle they have asked from gfg 20 top puzzles.
- Do you have any questions from me

1. Delete a Node from Linked List

Moderate

40m average time

67% success

0/80

Asked in companies

You have been given a linked list of integers. Your task is to write a function that deletes a node from a given position, 'POS'.

Note :

Assume that the Indexing for the linked list always starts from 0.

If the position is greater than or equal to the length of the linked list, you should return the same linked list without any change.

Illustration :

The following images depict how the deletion has been performed.

Image-I :

Image-II :

Problem approach

The fast solution is to copy the data from the next node to the node to be deleted and delete the next node. Something like this:

It is important to note that this approach will only work if it is guaranteed that the given pointer does not point to the last node. Because if it is the last node, then you don’t have a next node to copy the data from.

struct Node *temp = node_ptr->next;
node_ptr->data = temp->data;
node_ptr->next = temp->next;
free(temp);

Try solving now

2. Swap Adjacent Bit Pairs

Easy

10m average time

90% success

0/40

Asked in companies

You are given an integer 'N'. Your task is to find the number formed after swapping each even bit of 'N' in its binary representation with its adjacent bit on the right, assuming that the least significant bit is an odd bit.

For example :

Consider the integer N = 45 whose binary representation is 101101. The resulting number formed after swapping each even bit with its adjacent bit to the right will be 30 (011110) in this case.

Problem approach

Given an integer 'n' and two positions, i and j, you must swap the ith and jth bits of the number n.

You can solve this problem using the same logic we used in the last problem. The property of XOR - (a^b)^b = a or (a^b)^a = b.
We first extract the ith and jth bit and perform XOR. We then shift this XOR result in both the ith and jth positions to create a mask. We take this mask and complete the final XOR with the number n to get our final result.

Try solving now