Koolair Systems Interview Questions and Answers

Algorithm to find 2 numbers in an array whose sum is equal to a target integer

• Use a hash table to store the difference between target and each element in the array

• Iterate through the array and check if the current element exists in the hash table

• Return the pair of elements that sum up to the target integer

Write a select statement to retrieve work of all users who belong to my team.

• Join USERS and WORK tables on user_id

• Join MANAGERS and USERS tables on team

• Filter by manager_id

The manifest.json file contains the most important information of a Chrome extension.

• The manifest.json file includes the version number, permissions, content scripts, background scripts, and other important details.

• It is located in the root directory of the extension.

• It is required for all Chrome extensions.

• Example: "manifest_version": 2, "version": "1.0", "permissions": ["tabs", "storage"]

Hashtable is faster for finding an item than a sorted list.

• Hashtable has constant time complexity O(1) for finding an item.

• Sorted list has logarithmic time complexity O(log n) for finding an item.

• Hashtable uses hashing to directly access the item's location.

• Sorted list requires binary search to find the item's location.

• Hashtable is ideal for large datasets with frequent lookups.

• Sorted list is ideal for datasets that re

JSON and XML are the most popular data interchange formats when using APIs.

• JSON (JavaScript Object Notation) is a lightweight format that is easy to read and write. It is widely used in web APIs.

• XML (Extensible Markup Language) is a more complex format that is also widely used in web APIs.

• Other formats include CSV (Comma Separated Values), YAML (YAML Ain't Markup Language), and Protocol Buffers.

Popular APIs for Social Commerce services

• Facebook Graph API for social media integration

• Instagram API for photo sharing and tagging

• Twitter API for real-time updates and customer engagement

• Pinterest API for product discovery and sharing

• Google Maps API for location-based services

• PayPal API for secure payment processing

Use a script to iterate through each HTML page, locate phone numbers, and update their format.

• Write a script using a programming language like Python or JavaScript to iterate through each HTML page

• Use regular expressions to locate phone numbers in the pages

• Update the format of the phone numbers as needed (e.g. adding country code, changing separators)

• Save the updated HTML pages with the new phone number format

Designing Google Suggest system

• I would start by analyzing user search patterns and frequently searched keywords

• Then, I would create a database of these keywords and their associated search results

• I would use indexing services to quickly retrieve relevant results for each keyword

• I would also implement machine learning algorithms to improve the accuracy of suggestions over time

Check if a number is a power of 2 and odd.

• To check if a number is a power of 2, use bitwise AND operator with the number and its predecessor. If the result is 0, it is a power of 2.

• To check if a number is odd, use modulus operator with 2. If the result is 1, it is odd.

• Example code in Python:

• def is_power_of_two(num):

• return num & (num - 1) == 0

• def is_odd(num):

• return num % 2 == 1

By introducing new menu items, optimizing pricing strategy, and improving the overall dining experience.

• Conduct a survey to understand the preferences of employees

• Introduce healthy and affordable meal options

• Offer discounts for bulk orders or loyalty programs

• Partner with local vendors to source fresh ingredients

• Improve the ambiance and seating arrangements

• Implement online ordering and delivery services

Reviewing 30 million ads from 42 languages in Google AdWords and rejecting non-compliant ads requires a systematic approach.

• Create a set of specific rules and guidelines for ad compliance

• Use automated tools to filter out ads that violate the rules

• Assign a team of reviewers to manually check the remaining ads

• Ensure that the reviewers are fluent in the languages of the ads they are reviewing

• Regularly update the rules and...read more

Multiple data structures are used to print nodes in a specific order. One data structure cannot be used alone.

• The given order suggests a depth-first search traversal of a tree-like structure.

• A stack can be used to keep track of the nodes to be visited.

• A queue can be used to store the children of a node in the order they are visited.

• An array can be used to store the nodes in the required order.

• A linked list can be used ...read more

Find largest pen using minimum comparisons with tops.

• Divide pens into two groups and compare largest pen from each group with largest top.

• Repeat the process with the group containing the largest pen until only one pen is left.

• The remaining pen is the largest pen.

• Total number of comparisons required is 2n-3.

Given n dice with 'a' sides and sum b, return no. of ways to obtain b. Optimize time and space complexity.

• Use dynamic programming to reduce time complexity

• Create a 2D array to store the number of ways to obtain each sum for each number of dice

• Use rolling arrays to optimize space complexity

• Example: n=2, a=6, b=7 -> 6 ways to obtain sum 7

• Example: n=3, a=4, b=8 -> 21 ways to obtain sum 8

Sort 128 GB data on 2 machines with 64 GB RAM each. Extend to 1000 machines.

• Use external sorting algorithm like merge sort or quick sort

• Divide data into smaller chunks and sort them individually

• Merge sorted chunks using additional RAM

• For 1000 machines, use distributed sorting algorithms like MapReduce or Hadoop

• Ensure data consistency and fault tolerance in distributed sorting

Infrastructure in India is a high growth sector due to increasing urbanization, government initiatives, and foreign investments.

• India's urban population is expected to reach 600 million by 2030, leading to a demand for better infrastructure

• The government's initiatives like Smart Cities Mission, Bharatmala Project, and Sagarmala Project are driving infrastructure development

• Foreign investments in infrastructure projects...read more

India received $64 billion in FDI in 2020-21, a 10% increase from the previous year.

• India is one of the top FDI destinations in the world.

• Major sectors attracting FDI include services, computer software and hardware, and telecommunications.

• Singapore, Mauritius, and the United States are the top sources of FDI in India.

• The Indian government has implemented various policies to attract more FDI, such as liberalizing FDI n

I am a highly motivated and experienced professional with a passion for problem-solving and teamwork.

• I have a degree in computer science and have worked in the tech industry for 5 years.

• I am skilled in programming languages such as Java, Python, and C++.

• I have experience leading teams and collaborating with cross-functional teams.

• I am a quick learner and enjoy taking on new challenges.

• In my free time, I enjoy hiking an

Finance is a crucial aspect of any business, as it helps in managing and allocating resources effectively.

• Finance helps in making informed business decisions

• It helps in managing cash flow and allocating resources effectively

• Finance plays a key role in determining the financial health of a company

• It helps in raising capital for business expansion and growth

• Finance also involves risk management and financial planning

Deloitte's reputation for innovation, global reach, and diverse expertise sets it apart from other consulting firms.

• Deloitte has a strong focus on innovation and technology, which allows them to provide cutting-edge solutions to clients.

• Deloitte has a global network of offices and professionals, which enables them to provide services to clients in various regions and industries.

• Deloitte has a diverse range of expertise...read more

I would not take up a finance job if it does not align with my values and goals.

• Passion alone is not enough to sustain a fulfilling career.

• I prioritize finding a job that aligns with my values and goals.

• If a finance job does not align with my values and goals, it would not be a good fit for me.

• For example, if I am passionate about finance but also value work-life balance, I may not take up a high-stress finance job tha...read more

Yes, I have a few questions.

• Can you tell me more about the company culture?

• What are the main responsibilities of this role?

• Are there any ongoing projects I would be involved in?

• What is the typical career progression for a business analyst in this company?