3000+ Cognizant Interview Questions and Answers

Interview questions for Programmer Analyst position

• C# is a programming language used for developing Windows applications

• OOPS concepts include inheritance, encapsulation, abstraction, and polymorphism

• Delegate is a type that represents references to methods with a specific parameter list and return type

• Polymorphism is the ability of an object to take on many forms. Types include compile-time and runtime polymorphism

• Out and ref keywords are used for passing arguments by referenc...read more

Fix syntax and logical errors in maxReplace function

• Change 'o' to '0' in second for loop

• Replace sum with inputList[i] in second for loop

• Add a condition to check if inputList[i] is greater than sum in second for loop

• Print sum instead of inputList[i] in third for loop

Calculate the Nth Fibonacci number efficiently using dynamic programming.

• Use dynamic programming to store and reuse previously calculated Fibonacci numbers.

• Start with base cases F(1) and F(2) as 1, then calculate subsequent Fibonacci numbers.

• Optimize the solution to avoid redundant calculations by storing intermediate results.

• Time complexity can be reduced to O(N) using dynamic programming.

• Example: For N = 5, the 5th Fibonacci number is 5.

Quality refers to the degree of excellence or superiority of a product or service.

• Quality is subjective and can vary depending on the customer's expectations.

• It can be measured through various metrics such as defect rate, customer satisfaction, and reliability.

• For example, a high-quality car would have a low defect rate, high customer satisfaction, and be reliable.

• Quality is important for customer loyalty and brand reputation.

• Continuous improvement is necessary to maintain an...read more

Find pairs of elements in an array that sum up to a given value, sorted in a specific order.

• Iterate through the array and for each element, check if the complement (S - current element) exists in a hash set.

• Keep track of pairs in a hash set to avoid duplicates.

• Sort the pairs based on the criteria mentioned in the problem statement.

• Return the sorted list of pairs.

Calculate the time taken by a train to pass through a tunnel given its speed, length, and the tunnel's length.

• Convert the speed of the train from mph to miles per minute.

• Calculate the time taken by the front of the train to enter the tunnel.

• Calculate the time taken by the rear of the train to exit the tunnel.

• Subtract the time taken by the front from the time taken by the rear to get the total time taken.

• Add the units to the final answer.

Given a sorted alien dictionary in an array of strings, determine the character order of the alien language.

• Iterate through the words in the dictionary to build a graph of character dependencies.

• Perform a topological sort on the graph to determine the character order.

• Return the character array representing the order of characters in the alien language.

Determine the maximum profit that can be achieved by selling stocks with at most two transactions.

• Iterate through the array and calculate the maximum profit that can be achieved by selling at each day.

• Keep track of the maximum profit that can be achieved after the first transaction and the maximum profit that can be achieved after the second transaction.

• Return the maximum profit that can be achieved after the second transaction.

Stack is a data structure that follows LIFO (Last In First Out) principle. Converting a queue to stack requires dequeuing and pushing elements.

• Stack is a collection of elements with two main operations: push and pop.

• Push adds an element to the top of the stack, while pop removes the top element.

• Converting a queue to stack requires dequeuing all elements and pushing them onto a stack.

• Example: Queue: 1-2-3-4-5, Stack: 5-4-3-2-1

I would apologize for the delay and offer a solution or compensation.

• Acknowledge the inconvenience caused to the customer

• Explain the reason for the delay and assure them that steps are being taken to resolve it

• Offer a solution or compensation to make up for the delay

• Maintain open communication with the customer throughout the process

Java Developer interview questions covering array list, linkedlist, hashmap, synchronization, abstract vs interface, singleton class, Spring framework, database configuration, and Java 8 features.

• ArrayList and LinkedList differ in terms of implementation, performance, and usage

• HashMap uses hashing to store and retrieve key-value pairs

• Synchronized is used to ensure thread safety and prevent race conditions

• Abstract classes cannot be instantiated and can have both abstract and n...read more

The logic of the program is to reverse a given string word by word without using any built-in function.

• Split the string into an array of words using whitespace as the delimiter.

• Iterate through the array of words in reverse order.

• Append each word to a new string, separated by a space.

BPO stands for Business Process Outsourcing. Insurance refers to a contract between an individual and an insurance company.

• BPO involves outsourcing non-core business functions to a third-party provider

• Insurance is a means of protection against financial loss

• Types of insurance include life, health, auto, and property insurance

• Insurance companies collect premiums from policyholders and use the funds to pay out claims

• BPO services can be used in the insurance industry for tasks s...read more

Breach is a violation of a contract. It can result in legal action and damages.

• Breach occurs when one party fails to fulfill their obligations under a contract.

• It can be a material breach, which is a serious violation, or a minor breach.

• If a breach occurs, the non-breaching party can seek legal action and damages.

• For example, if a contractor fails to complete a project on time, the client may sue for damages.

• If an employee breaches a non-compete agreement, the employer may se...read more

I am proficient in multiple programming languages including Java, Python, and C++.

• Proficient in Java, Python, and C++

• Experience with web development languages such as HTML, CSS, and JavaScript

• Familiarity with scripting languages like Bash and PowerShell

• Knowledge of database languages like SQL and NoSQL

• Comfortable with object-oriented programming and design patterns

Spark plug ignites the fuel-air mixture in diesel engine to start combustion process.

• Spark plug creates a spark to ignite the fuel-air mixture in the combustion chamber

• This starts the combustion process which powers the engine

• Diesel engines usually have glow plugs to preheat the combustion chamber for easier ignition

The choice between 'call' and 'apply' in JavaScript depends on whether you have the arguments as an array or as individual parameters.

• Use 'call' when you have the arguments as individual parameters.

• Use 'apply' when you have the arguments as an array.

• Both 'call' and 'apply' allow you to invoke a function with a specific 'this' value.

Calculate minimum steps for a Knight to reach target position on a chessboard.

• Use BFS algorithm to find shortest path from Knight's starting position to target position.

• Consider all possible moves of the Knight on the chessboard.

• Keep track of visited positions to avoid revisiting them.

• Return the minimum number of moves required for the Knight to reach the target position.

Interview questions on SQL and ETL testing

• Row_Number, Rank, and Dense Rank are used for ranking and ordering data in SQL

• Defects/Bugs can be classified into different stages such as Open, In Progress, Resolved, Closed, etc.

• Schema objects are database objects such as tables, views, indexes, etc.

• Different types of loads in ETL Testing include Full Load, Incremental Load, and Delta Load

• Junk Dimension is a dimension table that contains low cardinality columns

• SQL to remove duplicat...read more

Minimize Hamming distance between two arrays by swapping elements at allowed indices.

• Iterate through allowed swaps and swap elements in ninja array accordingly.

• Calculate Hamming distance between ninja and enemies arrays after swaps.

• Return the minimum Hamming distance obtained.

Answers to common questions related to APIs, API management, and Apigee Edge

• API stands for Application Programming Interface and is a set of protocols and tools for building software applications

• APIs are popular because they allow different software systems to communicate and share data with each other

• API management involves the process of creating, publishing, documenting, and analyzing APIs

• Apigee Edge is an API management tool that provides features such as security, analyt...read more

The number of staging, dimension and fact tables in source and target systems need to be compared.

• Compare the number of staging, dimension and fact tables in source and target systems.

• Check if the table names and column names are consistent in both systems.

• Verify if the data types and data values are matching in both systems.

• Ensure that the ETL process is properly mapping the data from source to target systems.

• Perform data profiling to identify any discrepancies between the s...read more

1. Cut cake in 8 pieces in minimum cuts. 2. Make 4 equilateral triangles using 6 matchsticks.

• 1. Cut cake in half horizontally and vertically. Cut each quarter diagonally.

• 2. Use 3 matchsticks to form a triangle. Use the other 3 to connect the centers of each triangle.

• Both puzzles require creative thinking and problem-solving skills.

Answering questions related to OOP characteristics, polymorphism, and programming projects.

• OOP characteristics include inheritance, encapsulation, abstraction, and polymorphism.

• Abstraction is the process of hiding implementation details while encapsulation is the process of hiding data.

• Types of polymorphism include compile-time and runtime polymorphism.

• Projects mentioned in CV were discussed and explained.

• A program to find prime factors of a number can be written using a loop...read more

Find the maximum difference between any two elements in an array and determine if it is even or odd.

• Iterate through the array to find the maximum and minimum elements

• Calculate the difference between the maximum and minimum elements

• Check if the difference is even or odd and return the result

The task is to find the next greater element for each element in a list of integers.

• Iterate through the list of integers from right to left.

• Use a stack to keep track of elements whose next greater element is yet to be found.

• Pop elements from the stack until a greater element is found or the stack is empty.

• Assign the next greater element to the current element or -1 if no greater element is found.

• Return the list of next greater elements.

Java is platform independent due to its bytecode and JVM.

• Java code is compiled into bytecode which is platform-independent.

• JVM (Java Virtual Machine) interprets the bytecode and executes it on any platform.

• This eliminates the need for recompilation of code for different platforms.

• For example, a Java program compiled on Windows can run on Linux or Mac without any changes.

• This makes Java highly portable and flexible.

Calculate the minimum number of refueling stops needed for a ninja to reach a destination with given gas stations and starting fuel.

• Iterate through gas stations while maintaining current fuel level and number of stops made

• Refuel at each station if necessary to ensure enough fuel to reach the next station or destination

• Keep track of the minimum number of stops needed to reach the destination

Calculate the total sum of Hamming Distance for all possible pairs of elements in an array.

• Iterate through all pairs of elements in the array

• Calculate the Hamming Distance between each pair of elements

• Sum up all the calculated Hamming Distances

Print a star pattern based on the given non-negative integer 'N'.

• Iterate from 1 to N and print '*' in each row with increasing count

• Use nested loops to print spaces before the '*' in each row

• Ensure to print the correct number of spaces before the '*' in each row

• Handle the edge case where N is 0 separately

I have knowledge of the US healthcare system and its regulations.

• I am aware of the Affordable Care Act (ACA) and its impact on the healthcare industry.

• I understand the role of insurance companies and government programs like Medicare and Medicaid.

• I know about the various healthcare providers such as hospitals, clinics, and private practices.

• I am familiar with the electronic health record (EHR) system and its importance in healthcare.

• I have knowledge of healthcare data managem...read more

Merge overlapping intervals and return sorted list of merged intervals by start time.

• Iterate through intervals and merge overlapping ones

• Sort merged intervals by start time

• Return the sorted list of merged intervals

DFS traversal problem on an undirected and disconnected graph to find connected components.

• Use Depth First Search (DFS) algorithm to traverse the graph and find connected components.

• Maintain a visited array to keep track of visited vertices.

• For each unvisited vertex, perform DFS to explore all connected vertices and form a connected component.

• Repeat the process until all vertices are visited and print the connected components.

• Handle disconnected components by starting DFS fro...read more

Structures are value types while classes are reference types.

• Structures are allocated on stack while classes are allocated on heap.

• Structures do not support inheritance while classes do.

• Structures cannot have explicit parameterless constructors while classes can.

• Structures are used for small data structures while classes are used for larger, more complex objects.

• Example of structure: struct Point { int x, y; }

• Example of class: class Person { string name; int age; }

Answering questions related to programming language Python.

• I am familiar with Python programming language.

• Datasets in Python include NumPy, Pandas, and SciPy.

• List is mutable while Tuple is immutable in Python.

• Program to find number of white spaces in a given string: def count_spaces(string): return string.count(' ')

• While loop executes a block of code as long as the condition is true, for loop executes a block of code for a specific number of times.

The frog will require 98 jumps to get out of the well.

• The frog jumps 2m high but falls down 1m, so it covers a net distance of 1m with each jump.

• To calculate the number of jumps, we need to subtract the initial jump of 2m from the total depth of the well (100m).

• The remaining distance to cover is 100m - 2m = 98m.

• Since the frog covers 1m with each jump, it will require 98 jumps to cover the remaining distance and reach the top of the well.

Use Selenium WebDriver to find and count all text boxes on a web page.

• Use Selenium WebDriver to locate all text boxes on the web page

• Use findElements method with input tag and type attribute as text to find all text boxes

• Get the size of the list of elements to get the count of text boxes

Use SQL JOIN to fetch common records from two tables.

• Use SQL JOIN to combine the two tables based on a common column (e.g. student ID).

• Select the columns you want to retrieve from both tables.

• Use the WHERE clause to filter out the records that are common between the two tables.

Yes, I am aware of the formulas used in Excel.

• I am familiar with basic formulas such as SUM, AVERAGE, MAX, MIN, etc.

• I also know how to use more complex formulas such as VLOOKUP, IF statements, and nested functions.

• I am comfortable with creating and using named ranges, and using functions with cell references.

• I am also familiar with using Excel's built-in functions for statistical analysis and financial calculations.

• Overall, I am confident in my ability to use Excel to perform...read more

Technical Lead interview questions on computer system validation, documentation, security policy, data integrity, GAMP5, risk assessment, backup and restoration, software categories, and more.

• Types of documentation for computer system validation

• Recent/current software execution and computer system validation

• Security policy for GxP computerization system

• Traceability matrix and its purpose

• ALCOA and ALCOA+ principles

• Definition and importance of data integrity

• Regulatory points fo...read more

Reverse a given string containing alphabets, numbers, and special characters.

• Iterate through the string from the end to the beginning and append each character to a new string.

• Use built-in functions like reverse() or slicing to reverse the string.

• Handle special characters and numbers while reversing the string.

• Ensure to consider the constraints provided in the problem statement.

RDBMS is a type of DBMS that uses a relational model to store and manage data.

• DBMS is a general term for any software that manages data

• RDBMS uses tables with rows and columns to store data

• RDBMS enforces relationships between tables using keys

• Example: MySQL, Oracle, SQL Server

• Example of a database: a customer database for a retail store

Code to print prime numbers in right angle triangle format.

• Create a function to check if a number is prime or not.

• Use nested loops to print the numbers in right angle triangle format.

• Start with the first prime number and keep adding prime numbers to the triangle.

• Example: 2 3 5 7 11 13 17 19 23 29

Data structures are ways to organize and store data. Two examples are arrays and linked lists.

• Arrays are a collection of elements of the same data type, stored in contiguous memory locations.

• Linked lists are a collection of nodes, each containing data and a reference to the next node in the list.

Divide 1 kg cake equally among 8 people in 3 cuts.

• Cut the cake into 8 equal pieces using 2 cuts.

• Stack the pieces and cut them in half using the third cut.

• Distribute the 16 pieces among 8 people.

The task is to find the total number of ways to make change for a specified value using given denominations.

• Create a dynamic programming table to store the number of ways to make change for each value up to the target value.

• Iterate through each denomination and update the table accordingly.

• The final answer will be the value in the table at the target value.

• Consider edge cases like when the target value is 0 or when there are no denominations that can make the change.

• Example: ...read more

Display a pyramid star pattern for a given positive integer N with spaces in between.

• Iterate from 1 to N to print each row

• For each row, print N-i spaces followed by 2*i-1 stars

• Use nested loops to handle spaces and stars accordingly

Interview questions for Software Engineer position

• Describe recent project and technologies used

• Explain dependency injection and differences between Rest and Soap

• Differentiate Monolithic and Microservice architecture

• List features of Java 8 and write programs using Java 8

• Provide pseudo code for sorting a list of integers without using Java 8 sort method

• Define functional interface and its annotation

Sort an array of positive integers (0, 1, 2) in non-decreasing order.

• Iterate through the array and count the occurrences of 0, 1, and 2.

• Update the array with the counts of each element in non-decreasing order.

• Print the sorted array for each test case.

The challenge involves calculating bills for customers on Black Friday based on discounts for every 'Nth' customer.

• Implement 'blackFriday' function to initialize discount for every Nth customer

• Implement 'generateBill' function to calculate total bill for each customer's purchase

• Consider input constraints and generate final bill amounts for each customer in each test case

The primary feature to test in a train booking system would be the booking process.

• Test the ability to search for available trains and seats

• Test the ability to select and reserve seats

• Test the payment process

• Test the confirmation and ticket generation process

Count the number of islands in a 2D matrix of 1s and 0s.

• Use Depth First Search (DFS) or Breadth First Search (BFS) to traverse the matrix and identify connected groups of 1s.

• Maintain a visited array to keep track of visited cells to avoid revisiting them.

• Increment the island count each time a new island is encountered.

• Consider all eight possible directions for connectivity between cells.

• Handle edge cases like out of bounds indices and already visited cells.

Method and Function are both blocks of code that perform a specific task, but the main difference is that a method is associated with an object while a function is not.

• A method is called on an object, while a function is called independently.

• A method can modify the state of an object, while a function cannot.

• A method is defined within a class, while a function is defined outside of a class.

• Example of a method: object.methodName()

• Example of a function: functionName()

This interview question covers various topics including programming, design patterns, data structures, and exception handling in Java.

• Write a program to generate the Fibonacci series

• Write a program using boolean variables

• Explain the ClassCastException and how to handle it

• Discuss the Singleton design pattern and its implementation with different JDK versions

• Explain abstract classes and interfaces in your current project

• Explain hashing in HashMap and the number of buckets

• Differ...read more

A function is a block of code that performs a specific task and can be called multiple times.

• Functions help in modularizing code and making it reusable.

• Functions can take parameters and return values.

• Functions can be defined in different ways such as function declaration, function expression, arrow function, etc.

• Examples of functions include Math.max(), console.log(), and document.getElementById().

Program to check if a given string is palindrome or not using two pointers approach.

• Initialize two pointers, one at the start and one at the end of the string.

• Compare the characters at both pointers and move them towards each other until they meet.

• If all characters match, the string is a palindrome.

• If any character doesn't match, the string is not a palindrome.

Class is a blueprint for creating objects, encapsulation is the process of hiding data and methods within a class.

• Class is a template or blueprint that defines the properties and behaviors of an object.

• Encapsulation is the process of bundling data and methods together within a class, hiding the internal details from the outside world.

• Other features of OOP include inheritance, polymorphism, and abstraction.

• Inheritance allows a class to inherit properties and methods from anoth...read more

Union combines the result sets of two or more SELECT statements, while Union All combines all rows from two or more SELECT statements.

• Union removes duplicate rows, while Union All does not.

• Union requires the number and order of columns in all SELECT statements to be the same, while Union All does not have this requirement.

• Example: SELECT column1 FROM table1 UNION SELECT column1 FROM table2;

• Example: SELECT column1 FROM table1 UNION ALL SELECT column1 FROM table2;

Interview questions for Programmer Analyst role

• Explained automation framework used in the project

• Differentiated between Smoke, Sanity & Regression testing

• Answered scenario-based questions

• Discussed defect severity vs priority

• Explained BDD and Cucumber

• Answered basic questions on Selenium

The task is to determine if the encoding and decoding process of 'SECRET_INFORMATION' is successful.

• Read the number of test cases 'T'

• For each test case, encode the 'SECRET_INFORMATION' and then decode it

• Compare the decoded string with the original 'SECRET_INFORMATION'

• Print 'Transmission successful' if they match, else print 'Transmission failed'

Quick Sort is a divide and conquer algorithm that sorts an array in ascending order by choosing a pivot and partitioning the array into smaller subarrays.

• Choose a pivot element from the array.

• Partition the array into two subarrays - one with elements smaller than the pivot and one with elements larger than the pivot.

• Recursively apply the same process on the subarrays until the entire array is sorted.

• Complexity can be optimized to NlogN in the worst-case scenario.

Given a binary tree, determine and return its bottom view when viewed from left to right.

• Traverse the binary tree level by level and keep track of the horizontal distance and depth of each node

• For each horizontal distance, keep track of the node with the maximum depth

• Return the nodes in the bottom view from left to right

Create a class Person with private variables name and age, and methods to set and get their values.

• Create a class Person with private variables 'name' and 'age'.

• Implement a method setValue to set the variables' values.

• Implement a method getValue to print the variables' values.

• Ensure the name is a non-empty string and the age is a non-negative integer.

• Encapsulate the data and provide a clear interface for setting and getting the values.

The problem statement involves finding all possible paths for a rat to reach its destination in a maze.

• Create a recursive function to explore all possible paths from the starting position to the destination.

• Use backtracking to backtrack and explore other paths if the current path leads to a dead end.

• Mark the cells visited by the rat with 1 and unvisited cells with 0 in the output path.

• Ensure the rat can only move through cells marked as 1 in the maze.

• Consider constraints such...read more

Answering Salesforce Marketing Cloud Developer interview questions

• To bypass validation rule for a particular profile, use the $Profile global variable in the rule formula

• To update contact record upon account update, write a trigger on Account object and update related Contact records

• To fetch contact records without account, use SOQL query with LEFT JOIN on Account object and WHERE clause to filter null values

At landing and staging area, I will perform data validation to ensure accuracy and completeness of data.

• Validate data against source system

• Check for missing or duplicate data

• Verify data types and formats

• Ensure data integrity and consistency

• Perform data profiling and data quality checks

There are various algorithm methods in machine learning, such as supervised learning, unsupervised learning, and reinforcement learning.

• Supervised learning: Algorithms learn from labeled data to make predictions or classifications.

• Unsupervised learning: Algorithms learn from unlabeled data to discover patterns or relationships.

• Reinforcement learning: Algorithms learn through trial and error to maximize rewards.

• Other methods include semi-supervised learning, transfer learning,...read more

Program to check if a string starts with 's' and convert it to an array

• Use string method startsWith() to check if the string starts with 's'

• If it starts with 's', use split() method to convert it into an array

• Loop through the array and print each element

Object storage stores data as objects while block storage stores data as blocks.

• Object storage is ideal for unstructured data like images, videos, and documents.

• Block storage is ideal for structured data like databases and virtual machines.

• Object storage uses unique identifiers to access data while block storage uses block addresses.

• Object storage is more scalable and cost-effective than block storage.

• Examples of object storage include Amazon S3 and Google Cloud Storage while...read more

NDAs/CDAs are legal agreements that protect confidential information shared between parties.

• NDAs/CDAs stand for Non-Disclosure Agreements/Confidentiality Disclosure Agreements.

• They are used to protect sensitive information from being disclosed to unauthorized parties.

• The clauses in NDAs/CDAs typically include definitions of confidential information, obligations of the parties involved, duration of the agreement, and remedies for breach.

• Examples of clauses in NDAs/CDAs include...read more

The task is to find the contiguous subarray within an array with the highest product of its elements.

• Iterate through the array and keep track of the maximum and minimum product ending at each index.

• Update the maximum product by considering the current element, maximum product ending at the previous index multiplied by the current element, and minimum product ending at the previous index multiplied by the current element.

• Return the maximum product found during the iteration.

• Ex...read more

Given an integer 'N', find the final single-digit value by summing its digits iteratively.

• Iteratively sum the digits of the given integer until the result is a single-digit number

• Output the final single-digit integer for each test case

• Follow the constraints provided in the problem statement

Implement a function to determine if the binary representation of a given integer is a palindrome.

• Convert the integer to binary representation

• Check if the binary representation is a palindrome by comparing it with its reverse

• Return true if it is a palindrome, false otherwise

To remove redundancy in a database with repeated names, use normalization techniques.

• Identify the primary key of the table and ensure it is unique

• Create separate tables for related data to avoid repeating information

• Use foreign keys to link related tables

• Consider using indexing to improve performance

• Update existing data to conform to the new structure

Interview questions for Project Associate position covering OOPS concepts, MVC, ADO.NET, and SQL.

• Four pillars of OOPS: Abstraction, Encapsulation, Inheritance, Polymorphism

• Abstract class: Cannot be instantiated, can have abstract and non-abstract methods

• Interfaces: Contract that defines a set of methods, can be implemented by classes

• Finalize method: Called by garbage collector before object is destroyed

• Dispose method: Used to release unmanaged resources, should be called expl...read more

To select uncommon records that do not match, use the NOT IN or NOT EXISTS clause in SQL.

• Use the NOT IN clause to select records that do not match a specific list of values.

• Use the NOT EXISTS clause to select records that do not have a matching record in a subquery.

• Example: SELECT * FROM table_name WHERE column_name NOT IN (value1, value2);

• Example: SELECT * FROM table1 WHERE NOT EXISTS (SELECT * FROM table2 WHERE table1.id = table2.id);

Answers to technical interview questions on Java programming language.

• To display most frequent element in an array using Streams and Lambda expression, use Collectors.groupingBy() and Collectors.counting() methods.

• ArrayList is an ordered collection of elements while HashSet is an unordered collection of unique elements.

• Default methods in interface are used to provide a default implementation of a method that can be overridden by implementing classes.

• StringBuffer is synchroniz...read more

Design and implement a Least Recently Used (LRU) cache data structure supporting get and put operations with specified constraints.

• Implement a data structure for LRU cache with get and put operations

• Maintain a capacity limit and remove least recently used item when exceeding capacity

• Handle get operation by returning value for given key or -1 if key does not exist

• Handle put operation by inserting or updating key-value pair in cache

• Ensure time complexity is optimized for effici...read more

Print the left view of a binary tree given in level order form.

• Traverse the tree level by level and print the first node of each level

• Use a queue to keep track of nodes at each level

• Handle null nodes by using a placeholder value like -1

To change region of deployed AWS EC2 instance, create an AMI of the instance and launch it in the desired region.

• Create an AMI of the instance in the current region

• Copy the AMI to the desired region

• Launch the copied AMI in the desired region

Interview questions for Senior Associate position in ETL Testing

• Different types of schemas in ETL

• Examples of slowly changing dimensions

• Layers of ETL Testing and questions related to Staging layers

• Types of reports and dashboard for report testing

• Handling P1 defects in defect cycle

• SQL queries with different scenarios

The 4 pillars of OOP are Abstraction, Encapsulation, Inheritance, and Polymorphism.

• Abstraction: Hiding implementation details and showing only necessary information.

• Encapsulation: Binding data and functions together to prevent external interference.

• Inheritance: Creating new classes from existing ones, inheriting properties and methods.

• Polymorphism: Using a single interface to represent multiple types of objects.

OOPS Concepts, Fibonacci Series, Factorial, Call by value/reference, Abstraction, Encapsulation, Polymorphism, Switch, Router, Hub, OSI Model

• OOPS Concepts include inheritance, polymorphism, encapsulation, and abstraction

• Example of Fibonacci Series program: int fib(int n) { return (n <= 1) ? n : fib(n-1) + fib(n-2); }

• Example of Factorial program: int fact(int n) { return (n == 1 || n == 0) ? 1 : n * fact(n-1); }

• Call by value passes a copy of the variable, while call by referen...read more

The question asks for SQL queries for joining three tables, sorting in descending order in C program, and printing 'Hello, World!' in C.

• To join three tables in SQL, use the JOIN keyword with appropriate conditions.

• To sort in descending order in C, use the qsort() function with a custom comparison function.

• To print 'Hello, World!' in C, use the printf() function with the desired message.

Variables are names given to memory locations while objects are instances of a class with attributes and methods.

• Variables are used to store values while objects are used to represent real-world entities.

• Variables can be reassigned to different values while objects have a fixed identity.

• Variables are created when they are assigned a value while objects are created using constructors.

• Variables can be of different data types while objects are instances of a specific class.

• Examp...read more

To avoid re-rendering, use shouldComponentUpdate or React.memo

• Use shouldComponentUpdate to compare current and next props/state

• Use React.memo to memoize functional components

• Use useMemo to memoize expensive computations

• Use useCallback to memoize event handlers

• Use PureComponent for class components

What is the probability of picking a red ball out of 10 balls with 2 red, 5 blue, and 3 orange?

• There are 2 red balls out of 10 total balls

• The probability of picking a red ball is 2/10 or 1/5

• The probability can also be expressed as 20%

Count the number of subarrays whose combined strength matches the given enemy strength.

• Iterate through the array and maintain a running sum to check for subarrays with sum equal to the enemy strength.

• Use a hashmap to store the running sum frequencies and increment the count of subarrays accordingly.

• Return the count of subarrays that sum up to the given enemy strength.

Implement a function to encode a text message using run-length encoding.

• Iterate through the message and count consecutive characters

• Append the character and its count to the encoded message

• Handle edge cases like single characters or empty message

Availability zones and regions are geographical locations in AWS data centers.

• Availability zones are isolated locations within a region that contain their own power, cooling, and networking infrastructure.

• Regions are separate geographic areas that consist of two or more availability zones.

• Each region is completely independent and isolated from the others.

• Customers can deploy resources in multiple availability zones to achieve high availability and fault tolerance.

• Examples of ...read more

Address underperformance of team mate by identifying root cause and providing support.

• Have a conversation with the team mate to understand the root cause of underperformance

• Provide support and resources to help the team mate improve

• Set clear expectations and goals for the team mate

• Monitor progress and provide feedback regularly

• Consider involving a supervisor or HR if the issue persists

I rate my programming skills at 8 out of 10.

• I have experience in multiple programming languages such as Java, Python, and C++.

• I have completed several projects including a web application and a mobile app.

• I am constantly learning and improving my skills through online courses and personal projects.

Implement Merge Sort algorithm to sort a sequence of numbers in non-descending order.

• Understand the Merge Sort algorithm which involves dividing the array into two halves, sorting each half, and then merging them back together.

• Recursively apply the Merge Sort algorithm until the base case of having a single element in the array is reached.

• Merge the sorted halves back together in a way that maintains the non-descending order of the elements.

• Ensure to handle the input constrain...read more

One apple is still left in the basket because one of the people in the room is the owner of the basket and did not take an apple.

• One person in the room is the owner of the basket

• The owner did not take an apple

• Hence, one apple is still left in the basket

S3 is a cloud-based object storage service provided by Amazon Web Services (AWS).

• S3 stands for Simple Storage Service.

• It allows users to store and retrieve data from anywhere on the web.

• S3 offers different storage classes such as Standard, Infrequent Access, and Glacier.

• Standard is for frequently accessed data, Infrequent Access is for data that is accessed less frequently, and Glacier is for long-term archival storage.

• S3 also provides features like versioning, lifecycle poli...read more

To create a stored procedure that returns a table, use SELECT statement within the procedure.

• Create a stored procedure using CREATE PROCEDURE statement.

• Within the procedure, use SELECT statement to query the data and return the table.

• Specify the columns to be returned in the SELECT statement.

• Execute the stored procedure to retrieve the table data.

The query finds the employee name who earns the maximum salary.

• Use the SELECT statement to retrieve the employee name and salary from the database table.

• Use the ORDER BY clause to sort the results in descending order based on salary.

• Use the LIMIT clause to limit the result to only one row.

• Return the employee name from the query result.

Object oriented programming is a programming paradigm that focuses on objects and their interactions to solve problems.

• Encapsulation: bundling data and methods that operate on that data within a single unit.

• Inheritance: creating new classes from existing ones, inheriting their properties and methods.

• Polymorphism: the ability of objects to take on many forms, allowing them to be used in different ways.

• Abstraction: hiding implementation details and only showing the necessary in...read more