Lam Research Software QA Engineer Interview Questions and Answers

Use bitwise operations to find the sum of two numbers without using mathematical operators.

• Use bitwise XOR to find the sum of two numbers without carrying.

• Use bitwise AND and left shift to find the carry.

• Repeat the process until there is no carry left.

To delete a node from a linked list when only given a reference to the node, we can copy the data of the next node to the given node and delete the next node.

• Copy the data of the next node to the given node

• Update the next pointer of the given node to skip the next node

• Delete the next node

UDP is preferred over TCP in this project due to its low latency and lightweight nature.

• UDP is a connectionless protocol, which means it does not establish a direct connection between the sender and receiver.

• UDP is faster than TCP as it does not have the overhead of establishing and maintaining a connection.

• UDP is suitable for applications where real-time data transmission is crucial, such as video streaming or online ...read more

To clear the 7th bit in a 32-bit register, perform a bitwise AND operation with a mask that has all bits set to 1 except the 7th bit.

• Create a mask with the 7th bit set to 0 and all other bits set to 1

• Perform a bitwise AND operation between the register and the mask

• Store the result back in the register

The question asks to fill the blanks in a pyramid where each number is the sum of the numbers in the bottom two cells.

• Start from the bottom row and work your way up, calculating the sum of the numbers in the bottom two cells for each blank space.

• Use a loop to iterate through each row and column of the pyramid.

• Store the calculated sum in the corresponding blank space.

• Repeat the process until all the blanks are filled.

Moore's Law is the observation that the number of transistors in a dense integrated circuit doubles about every two years.

• Named after Intel co-founder Gordon Moore

• First stated in 1965

• Has been a driving force behind technological advancements

• Predicts exponential growth in computing power

• Has been challenged in recent years due to physical limitations

A process is an instance of a program while a thread is a subset of a process.

• A process has its own memory space while threads share memory space

• Processes are heavyweight while threads are lightweight

• Processes communicate through inter-process communication while threads communicate through shared memory

• Examples of processes include web browsers, text editors, etc. while examples of threads include GUI updates, backgro

Multi-core processors provide faster and more efficient computing.

• Improved performance and speed

• Ability to handle multiple tasks simultaneously

• Reduced power consumption

• Better multitasking capabilities

• Enhanced user experience

• Examples: Intel Core i7, AMD Ryzen 9

I am a software engineer with a loving family.

• I have been working as a software engineer for 5 years.

• My wife is a teacher and we have two children.

• We enjoy spending time together outdoors and traveling.

• My parents live in a different state but we keep in touch regularly.

• Family is very important to me and I prioritize spending time with them.

Developed a web-based project management tool and a mobile app for tracking expenses

• Created a responsive UI using React and Bootstrap

• Implemented user authentication and authorization using Firebase

• Integrated Google Maps API for location tracking in the mobile app

• Used Node.js and MongoDB for backend development

• Collaborated with a team of four to complete the projects

I have 5 years of experience in software engineering with expertise in Java and Python.

• Developed and maintained web applications using Java and Spring framework

• Designed and implemented RESTful APIs using Python and Flask

• Worked on database management and optimization using MySQL and MongoDB

• Collaborated with cross-functional teams to deliver high-quality software products

• Participated in code reviews and provided construc

My academic interests include computer science, artificial intelligence, and machine learning.

• Computer science

• Artificial intelligence

• Machine learning

Explain Big O notation

• Big O notation is used to describe the time complexity of an algorithm

• It helps us understand how the algorithm's performance changes with input size

• O(1) means constant time, O(n) means linear time, O(n^2) means quadratic time

• We want algorithms with lower Big O values for better performance

I am open to relocation based on the job opportunity and growth prospects.

• Open to relocation for the right opportunity

• Willing to move for career growth

• Flexible with location based on job requirements

Yes, I would love to have a pizza slice!

• I am a big fan of pizza and would never say no to a slice!

• Pizza is the perfect food for any occasion, whether it's a quick lunch or a late-night snack.

• I particularly enjoy pepperoni and mushroom pizza, but I'm open to trying new toppings as well.

Need more context. What needs to be done with the large rectangle?

• What are the dimensions of the rectangle?

• Is it a 2D or 3D object?

• What is the context of the problem?

• Are there any constraints or limitations?

• What tools or programming languages can be used?

Derive a formula to determine how many smaller rectangles fit into a bigger rectangle given their dimensions.

• Calculate the number of times the smaller rectangle can fit into the bigger rectangle horizontally and vertically

• Divide the width of the bigger rectangle by the width of the smaller rectangle to get the horizontal count

• Divide the height of the bigger rectangle by the height of the smaller rectangle to get the ve...read more

At least 4 points are required to draw a rectangle.

• A rectangle has 4 sides and 4 corners, so at least 4 points are needed to define those corners.

• The points must be arranged in a specific order to form a closed shape with 4 sides.

• Additional points can be used to add details or modify the shape of the rectangle.

• The number of points required may vary depending on the software or tool used to draw the rectangle.

Answering how to calculate new coordinates of a scaled rectangle and providing a program for it.

• To calculate new coordinates, multiply the original coordinates by the scaling factor

• Scaling factor can be calculated by dividing the new length/breadth by the original length/breadth

• Program can take input of original coordinates, scaling factor, and output new coordinates

• Example: Original coordinates: (0,0), (0,5), (5,5), (...read more

malloc is a function in C that dynamically allocates memory on the heap. It is used to allocate memory for variables or data structures.

• malloc is used in C programming language.

• It is used to allocate memory on the heap.

• malloc is different from 'new' in C++ as it does not call constructors for objects.

C++ is a general-purpose programming language while Objective C is a superset of C used for iOS and macOS development.

• C++ is widely used for developing applications, games, and system software.

• Objective C is mainly used for iOS and macOS development.

• C++ supports both procedural and object-oriented programming paradigms.

• Objective C is an object-oriented language with dynamic runtime features.

• C++ has a larger community a...read more

Class container is a class that holds objects of other classes, while class composition is a way to combine multiple classes to create a new class.

• Class container holds objects of other classes, acting as a collection or container.

• Class composition combines multiple classes to create a new class with its own behavior and attributes.

• In class container, the objects are typically stored in a data structure like an array o...read more

Divide the horses into groups of 5 and race them. Take the top 2 from each race and race them again. Finally, race the top 2 horses to determine the top 3.

• Divide the horses into 3 groups of 5 and race them.

• Take the top 2 horses from each race and race them again.

• Finally, race the top 2 horses to determine the top 3.

Developing a real-time data processing system for a high-traffic e-commerce website

• Implemented a distributed system architecture to handle large volumes of data

• Optimized algorithms for efficient data processing and storage

• Utilized caching mechanisms to improve system performance

• Worked closely with cross-functional teams to troubleshoot and resolve issues

• Example: Successfully reduced data processing time by 50% by imple

Seeking new challenges and opportunities for growth.

• Looking for a more challenging role to further develop my skills

• Interested in exploring new technologies and industries

• Seeking better career advancement opportunities

• Want to work in a more collaborative team environment

The width of a tree is the maximum number of nodes at any level in the tree.

• To calculate the width of a tree, we can perform a level order traversal and keep track of the maximum number of nodes at any level.

• We can use a queue data structure to perform the level order traversal.

• At each level, we count the number of nodes in the queue and update the maximum width if necessary.

Phases of compiler include lexical analysis, syntax analysis, semantic analysis, code generation, and optimization.

• Lexical analysis: breaking down input into tokens

• Syntax analysis: checking if tokens form valid syntax

• Semantic analysis: checking if syntax is semantically correct

• Code generation: generating machine code from input

• Optimization: improving generated code performance

C is preferred over C++ for certain applications due to its simplicity and efficiency.

• C is a simpler language compared to C++ and has a smaller runtime footprint.

• C is often used for low-level programming, embedded systems, and operating systems.

• C allows for more control over memory management and can be faster in certain scenarios.

• C++ introduces additional features like object-oriented programming and templates, which

Classes are blueprints for creating objects, while structures are similar but with different default access levels.

• Classes and structures are used to define the structure and behavior of objects in object-oriented programming.

• Classes are reference types and are allocated on the heap, while structures are value types and are allocated on the stack.

• Memory allocation for classes is managed by garbage collection, while mem...read more

Design logical circuits for arithmetic circuits in a blackbox.

• Understand the functionality of the arithmetic circuits in the blackbox.

• Identify the inputs and outputs of the blackbox.

• Design logical circuits using logic gates to replicate the arithmetic operations.

• Test the logical circuits to ensure they produce the same outputs as the arithmetic circuits.

Recursion in embedded C-code allows a function to call itself, useful for repetitive tasks or complex algorithms.

• Ensure proper base case to avoid infinite recursion

• Use stack space efficiently as embedded systems have limited resources

• Avoid recursive functions with deep call stacks to prevent stack overflow

• Example: Recursive function to calculate factorial of a number