50+ Coditas Technologies Interview Questions and Answers

To pour exactly 9 liters of water into a 12-liter gallon using 5 and 3-liter gallons.

• Fill the 5-liter gallon and pour it into the 12-liter gallon.

• Fill the 5-liter gallon again and pour it into the 12-liter gallon until it is full, leaving 1 liter in the 5-liter gallon.

• Empty the 12-liter gallon and pour the remaining 1 liter from the 5-liter gallon into it.

• Fill the 5-liter gallon again and pour it into the 12-liter gallon to get exactly 9 liters.

There are multiple ways to measure a 3 storeyed building, including using a measuring tape, laser distance meter, or counting the number of steps.

• Using a measuring tape to measure the height of each storey and adding them up.

• Using a laser distance meter to calculate the total height of the building.

• Counting the number of steps from the ground floor to the top floor and multiplying by the height of each step.

• Estimating the height based on the standard height of a storey in the...read more

Two programs to find the occurrence of a letter in a string using arrays and lists.

• For array program, iterate through the string and count the occurrence of the given letter.

• For list program, convert the string to a list and use the count() method to find the occurrence of the given letter.

• Handle edge cases like empty string and invalid input.

Extract numbers from a string of alphanumeric characters.

• Iterate through each character in the string and check if it is a number.

• Build a new string with only the numbers found in the original string.

• Return the final string containing only the numbers.

To add a link to your Linkedin account in a website by clicking on the logo, use the <a> tag with the href attribute set to your Linkedin profile URL.

• Use the <a> tag with the href attribute set to your Linkedin profile URL

• Insert the Linkedin logo image inside the <a> tag as the clickable element

• Example: <a href='https://www.linkedin.com/in/yourprofile'><img src='linkedin_logo.png' alt='Linkedin'></a>

Finally block is used to execute code after try-catch block, regardless of whether an exception is thrown or not.

• Finally block is optional and follows the catch block.

• It is used to clean up resources like closing files, database connections, etc.

• Finally block is executed even if an exception is not caught.

• It is used to ensure that a certain piece of code is always executed.

• Example: try { //code } catch (Exception e) { //exception handling } finally { //cleanup code }

The choice of database depends on factors like data structure, scalability, performance, and query requirements.

• Consider the data structure and relationships between entities.

• Evaluate the scalability requirements of the task.

• Analyze the performance needs, including read and write operations.

• Assess the query requirements, such as complex joins or aggregations.

• Examples: relational databases for structured data, NoSQL for unstructured or rapidly changing data.

The task is to add the consecutive numbers present in a given string.

• Iterate through the string character by character

• Check if the current character is a digit

• If it is a digit, continue iterating until a non-digit character is encountered

• Convert the consecutive digits into a number and add it to the sum

• Repeat the process until all characters are processed

• Return the sum

JDBC is a Java API for connecting and executing queries on a database.

• JDBC stands for Java Database Connectivity.

• It provides a set of classes and interfaces to interact with databases.

• JDBC allows developers to write database-independent code.

• It supports various database operations like connecting, querying, updating, and deleting data.

• JDBC drivers are used to establish a connection between Java application and database.

• Example: Class.forName("com.mysql.jdbc.Driver");

Sets are unordered collections of unique elements while lists are ordered collections of elements.

• Sets do not allow duplicate elements while lists do.

• Sets do not maintain the insertion order while lists do.

• Sets have faster lookup time for specific elements while lists have faster iteration time.

• Examples of sets in Java include HashSet and TreeSet while examples of lists include ArrayList and LinkedList.

Developed a web-based project management tool for small businesses

• Used PHP and MySQL for backend development

• Implemented a responsive UI using HTML, CSS, and JavaScript

• Included features such as task assignment, progress tracking, and file sharing

• Conducted user testing and incorporated feedback for improvements

Encapsulation, Inheritance, Polymorphism, Abstraction are the four pillars of OOPS

• Encapsulation: Bundling data and methods that operate on the data into a single unit. Example: Class Car with properties like make, model, and methods like start(), stop().

• Inheritance: Ability of a class to inherit properties and behavior from another class. Example: Class SUV inheriting from Class Car.

• Polymorphism: Ability to present the same interface for different data types. Example: Method ...read more

Python is a high-level, interpreted programming language known for its simplicity and readability.

• Python uses indentation to define code blocks, making it easier to read and understand.

• Python has a large standard library with built-in functions and modules for various tasks.

• Python supports multiple programming paradigms, including procedural, object-oriented, and functional programming.

• Python is dynamically typed, meaning variable types are determined at runtime.

• Python is pop...read more

Code to get unique elements of an array of strings

• Create a Set to store unique elements

• Iterate through the array and add elements to the Set

• Convert the Set back to an array to get unique elements

List is mutable, tuple is immutable. Use tuple for fixed data, list for changing data. To swap integers, use tuple unpacking.

• List can be modified, tuple is fixed

• List uses square brackets [], tuple uses parentheses ()

• To swap integers, use tuple unpacking: a, b = b, a

C++ supports multiple inheritance while Java supports single inheritance.

• C++ allows a class to inherit from multiple classes, while Java only allows a class to inherit from a single class.

• In C++, a class can have multiple parent classes, resulting in a complex class hierarchy.

• Java enforces single inheritance to avoid the diamond problem and maintain simplicity.

• For example, in C++, a class can inherit from both a 'Vehicle' class and a 'Animal' class, while in Java, it can only...read more

SQL databases are structured and use a fixed schema, while NoSQL databases are unstructured and have a flexible schema.

• SQL databases use structured query language for defining and manipulating the data.

• NoSQL databases use various data models like key-value, document, columnar, or graph.

• SQL databases are suitable for complex queries and transactions.

• NoSQL databases are horizontally scalable and provide high performance for large datasets.

• SQL databases ensure data integrity wit...read more

Relational databases store data in tables with predefined relationships. Non-relational databases store data in flexible, schema-less formats.

• Relational databases: MySQL, Oracle, SQL Server

• Non-relational databases: MongoDB, Cassandra, Redis

• Relational databases use structured query language (SQL) for data manipulation

• Non-relational databases provide high scalability and flexibility

• Relational databases are suitable for complex, structured data

• Non-relational databases are suitab...read more

Explaining the differences between ENTRYPOINT, CMD, and RUN in Docker and the usage of ARGS and ENV.

• ENTRYPOINT is the command that runs when the container starts

• CMD is the default command that runs after ENTRYPOINT, can be overridden

• RUN executes commands during the build process

• RUN can be used instead of CMD, but it will not be the default command

• ARGS are used to pass arguments to the Dockerfile during build time

• ENV sets environment variables that can be used in the Dockerfil...read more

OOPS (Object-Oriented Programming) is a programming paradigm based on the concept of objects, which can contain data and code.

• OOPS focuses on creating objects that interact with each other to solve a problem

• It involves concepts like classes, objects, inheritance, polymorphism, and encapsulation

• Example: Inheritance allows a class to inherit properties and behavior from another class

OOP stands for Object-Oriented Programming. Its five pillars are encapsulation, inheritance, polymorphism, abstraction, and composition.

• Encapsulation: Bundling data and methods that operate on the data into a single unit (object).

• Inheritance: Creating new classes by inheriting attributes and methods from existing classes.

• Polymorphism: Objects of different classes can be treated as objects of a common superclass.

• Abstraction: Hiding complex implementation details and showing on...read more

Database management features include data storage, retrieval, indexing, and security.

• Data storage: ability to store large amounts of data efficiently

• Data retrieval: ability to quickly access and retrieve specific data

• Indexing: optimizing data retrieval by creating indexes on columns

• Security: ensuring data is protected from unauthorized access

Sorting an array of strings

• Use a sorting algorithm like quicksort or mergesort

• Consider the length of the strings for comparison

• Use a comparator function to define custom sorting criteria

SQL select query syntax and types of join

• SQL SELECT query syntax: SELECT column1, column2 FROM table_name WHERE condition

• Types of joins: INNER JOIN, LEFT JOIN, RIGHT JOIN, FULL JOIN

• Example: SELECT orders.order_id, customers.customer_name FROM orders INNER JOIN customers ON orders.customer_id = customers.customer_id

Python code to find repeated numbers and their concurrency

• Iterate through the array and use a dictionary to store the count of each number

• Iterate through the dictionary to find numbers with count greater than 1 and their concurrency

Python is a high-level programming language known for its simplicity and readability.

• Python is an interpreted language, meaning it does not need to be compiled before running.

• It has a large standard library that provides many pre-built functions and modules.

• Python supports multiple programming paradigms, including procedural, object-oriented, and functional programming.

• It is widely used in various domains such as web development, data analysis, artificial intelligence, and au...read more

div is a block-level element while span is an inline element in HTML.

• div is used to group block-level elements and create sections on a webpage.

• span is used to style inline elements or group text within a block-level element.

• div elements create a line break before and after the element, while span does not.

Create a Directed Acyclic Graph (DAG) to execute Python scripts in parallel.

• Define tasks for each Python script to be executed in parallel

• Use a parallelism parameter to specify the number of tasks to run concurrently

• Set up dependencies between tasks to ensure proper execution order

• Use a DAG scheduler like Apache Airflow to manage and execute the DAG

Verification ensures that the product is built according to the design specifications, while validation ensures that the product meets the customer's needs and requirements.

• Verification checks if the product is being built correctly, while validation checks if the right product is being built.

• Verification is a process of evaluating the intermediate work products, while validation is a process of evaluating the final product.

• Verification is done before validation.

• Examples of v...read more

Sanity and smoke are types of testing in software engineering.

• Sanity testing is a quick test to check if the major functionalities of the application are working after a small change is made.

• Smoke testing is a quick test to check if the application is stable enough to proceed with further testing.

• Sanity testing is done to ensure that the application is ready for further testing.

• Smoke testing is done to ensure that the application is stable enough to proceed with further testi...read more

Types of databases include relational, NoSQL, object-oriented, and graph databases.

• Relational databases store data in tables with predefined schemas, using SQL for querying (e.g. MySQL, Oracle)

• NoSQL databases are schema-less and provide flexible data models (e.g. MongoDB, Cassandra)

• Object-oriented databases store objects as they are, with support for inheritance and encapsulation (e.g. db4o)

• Graph databases use nodes and edges to represent relationships between data (e.g. Neo4...read more

Rate in skills out of 5

• Programming: 5

• Data Analysis: 4

• Database Management: 4

• Machine Learning: 3

A header is a piece of information at the beginning of a data packet or file that contains details about the data.

• Headers are used in communication protocols to provide information about the data being transmitted.

• Headers typically include metadata such as the source and destination addresses, data type, and size.

• In HTTP, headers are used to pass additional information between the client and server, such as cookies or authentication tokens.

Explode function is used to split a string into an array of strings based on a delimiter.

• The explode function takes in a delimiter and a string as input

• It splits the string into an array of strings based on the delimiter

• For example, explode(',', 'apple,banana,orange') would return ['apple', 'banana', 'orange']

I have worked on a variety of technologies including Python, SQL, Hadoop, Spark, and AWS.

• Python

• SQL

• Hadoop

• Spark

• AWS

Polymorphish is a term used to describe the ability of a programming language to allow different data types to be used interchangeably.

• Polymorphish allows for flexibility in coding by allowing variables to hold different types of data.

• It is a key feature in object-oriented programming languages like Java and C++.

• For example, a function can accept different types of parameters and return different types of values based on the input.

Overriding is a concept in object-oriented programming where a subclass provides a specific implementation of a method that is already provided by its superclass.

• Overriding allows a subclass to provide a specific implementation of a method that is already defined in its superclass.

• The method in the subclass must have the same name, return type, and parameters as the method in the superclass to override it.

• Example: class Animal { void makeSound() { System.out.println('Animal s...read more

Inheritance is a concept in object-oriented programming where a class inherits attributes and methods from another class.

• Allows a class to inherit properties and behaviors from another class

• Promotes code reusability and reduces redundancy

• Creates a parent-child relationship between classes

• Derived class can access public and protected members of the base class

• Example: Class 'Car' can inherit from class 'Vehicle' to reuse common attributes like 'color' and 'speed'

Find the most frequent element in an array of strings.

• Create an object to store the frequency of each element in the array.

• Iterate through the array and update the frequency count in the object.

• Find the element with the highest frequency in the object.

I have 5 years of experience working with financial systems, including implementing new systems and analyzing data.

• Implemented a new financial system for a large corporation, resulting in improved efficiency and accuracy

• Analyzed financial data to identify trends and make recommendations for cost savings

• Worked closely with finance and IT teams to ensure smooth integration of new systems

• Experience with various financial software such as SAP, Oracle, and QuickBooks

Learnings from past project include importance of clear communication, stakeholder engagement, and thorough requirements gathering.

• Clear communication is key to ensure all team members are on the same page

• Engaging stakeholders early and often helps in managing expectations and gaining buy-in

• Thorough requirements gathering is essential to avoid scope creep and ensure project success

Sessions in MVC are used to store user-specific data across multiple requests.

• Sessions are used to maintain state between HTTP requests in MVC applications.

• Session data is stored on the server and can be accessed by the client using a session ID.

• Sessions can be used to store user authentication information, shopping cart items, etc.

Keywords in C# are reserved words that have special meaning and cannot be used as identifiers.

• Keywords are predefined and cannot be changed or redefined.

• Examples of keywords in C# include 'class', 'int', 'void', 'if', 'else', 'for', 'while', etc.

• Keywords are case-sensitive.

Arrays are a data structure that stores a collection of elements of the same data type in a contiguous memory location.

• Arrays are used to store multiple values in a single variable.

• Elements in an array are accessed by their index position.

• Arrays can be of fixed size or dynamic size.

• Example: String[] names = {"Alice", "Bob", "Charlie"};

Find duplicates in a list of elements.

• Iterate through the list and keep track of elements seen so far

• If an element is already in the seen elements, it is a duplicate

• Use a hash set to efficiently check for duplicates

Check if any two strings in the list are anagrams of each other

• Iterate through the list and for each string, sort the characters and check if it already exists in a hashmap

• If it exists, then the current string is an anagram of the existing string

• Return true if anagrams are found, false otherwise

Return unique elements from an array of strings

• Use Set to store unique elements

• Convert array to Set and then back to array to get unique elements

• Example: ['apple', 'banana', 'apple', 'orange'] should return ['apple', 'banana', 'orange']

Closures in JavaScript allow functions to access variables from an outer function even after the outer function has finished executing.

• Closures are created when a function is defined within another function and the inner function references variables from the outer function.

• Closures have access to the outer function's scope chain, allowing them to access variables even after the outer function has returned.

• Closures are commonly used in event handlers, callbacks, and for data ...read more

ArrayList is a dynamic array in Java that can grow or shrink in size as needed.

• ArrayList is a class in Java that implements the List interface.

• It allows for dynamic resizing, unlike regular arrays which have a fixed size.

• Elements in an ArrayList can be accessed using their index.

• Example: ArrayList names = new ArrayList();

• names.add("Alice"); names.add("Bob");

A todo list application built using ReactJS

• Use React components to create a form for adding new todos

• Store todos in state and map over them to display in a list

• Implement functionality to mark todos as complete and delete them

• Utilize CSS for styling and make the app responsive