100+ Software Engineer Trainee Interview Questions and Answers for Freshers

GraphQL is a query language for APIs and a runtime for executing those queries.

• GraphQL allows clients to request only the data they need.

• It provides a single endpoint for all data fetching.

• GraphQL schemas define the types of data that can be queried.

High order functions are functions that can take other functions as arguments or return functions as results.

• High order functions can accept functions as parameters.

• High order functions can return functions as output.

• Examples include map, filter, and reduce functions in JavaScript.

Yes, I am open to signing a bond.

• Signing a bond shows commitment and dedication to the company.

• It may involve a financial agreement or a commitment to work for a certain period of time.

• Signing a bond can provide opportunities for professional growth and development.

• Examples of bonds include training bonds, service bonds, or employment bonds.

Async wait function code example

• Use async/await keywords in the function declaration

• Use setTimeout to simulate asynchronous operation

• Return a Promise that resolves after a specified time

Polymorphism is the ability of an object to take on many forms.

• Polymorphism allows objects of different classes to be treated as if they are of the same class.

• There are two types of polymorphism: compile-time (method overloading) and runtime (method overriding).

• Compile-time polymorphism is achieved through method overloading, where multiple methods have the same name but different parameters.

• Runtime polymorphism is achieved through method overriding, where a subclass provides...read more

For loop is used when the number of iterations is known, while loop is used when the condition is true.

• For loop is used when the number of iterations is known beforehand.

• While loop is used when the condition needs to be checked before each iteration.

• For loop is more concise and easier to read for iterating over a range of values.

• While loop is more flexible as it allows for more complex conditions to be checked.

Monotype is a typeface design company that creates and licenses fonts for digital and print media.

• Monotype is a leading provider of typeface design and technology solutions.

• It offers a wide range of fonts for various applications, including web, mobile, and desktop.

• Some of the popular typefaces created by Monotype include Helvetica, Times New Roman, and Arial.

• Monotype also provides font management software and services to help customers optimize their typography.

• The company h...read more

A pointer is a variable that stores the memory address of another variable.

• Pointers allow for dynamic memory allocation and manipulation.

• They are commonly used in C and C++ programming languages.

• Example: int *ptr; ptr = # *ptr = 10; //num now has a value of 10

• Pointers can also be used to pass variables by reference in function calls.

A closure is a function that has access to its own scope, as well as the outer scope in which it was defined.

• A closure allows a function to access variables from an outer function even after the outer function has finished executing.

• Closures are commonly used in JavaScript for data encapsulation and creating private variables.

• Example: function outerFunction() { let outerVar = 'I am outer'; return function innerFunction() { console.log(outerVar); }; }

Reverse a string using sorting algorithm and perform preorder traversal for a tree.

• To reverse a string using sorting algorithm, we can convert the string to an array of characters, sort the array in descending order, and then join the characters back together to form the reversed string.

• For preorder traversal of a tree, we visit the root node first, then recursively traverse the left subtree and finally the right subtree.

WeakMap and WeakSet are specialized collections in JavaScript that allow for weak references to objects.

• WeakMap allows for mapping of objects to values where the object keys are weakly referenced.

• WeakSet is a collection of objects where the objects are weakly referenced.

• Weak references allow for objects to be garbage collected if they are no longer referenced elsewhere.

• WeakMap and WeakSet are useful for scenarios where you want to associate data with an object without prevent...read more

Keys and joins are important concepts in DBMS.

• Keys are used to uniquely identify a record in a table.

• Primary key is a unique identifier for a table.

• Foreign key is a reference to a primary key in another table.

• Joins are used to combine data from two or more tables based on a related column.

• Inner join returns only the matching records from both tables.

• Left join returns all records from the left table and matching records from the right table.

• Right join returns all records from ...read more

Types of machine learning include supervised, unsupervised, and reinforcement learning, each with unique use cases.

• Supervised learning: Uses labeled data to train a model to make predictions. Example: spam email detection.

• Unsupervised learning: Finds patterns in unlabeled data. Example: customer segmentation.

• Reinforcement learning: Learns through trial and error to maximize rewards. Example: game playing AI.

ArrayList is a resizable array implementation while HashSet is a collection of unique elements with no duplicate values.

• ArrayList allows duplicate elements and maintains insertion order.

• HashSet does not allow duplicate elements and does not maintain insertion order.

• ArrayList uses indexes to access elements while HashSet uses hashing for fast retrieval.

• Example: ArrayList list = new ArrayList<>(); HashSet set = new HashSet<>();

Final keyword restricts modification while static keyword is used for class-level variables and methods.

• Final keyword is used to make a variable constant and cannot be modified once initialized.

• Final keyword can also be used to make a method un-overridable in a subclass.

• Static keyword is used to declare class-level variables and methods.

• Static variables are shared among all instances of a class.

• Static methods can be called without creating an instance of the class.

Binary search is a technique used to efficiently locate a target value within a sorted array.

• Start by comparing the target value to the middle element of the array.

• If the target value is less than the middle element, search the left half of the array.

• If the target value is greater than the middle element, search the right half of the array.

• Repeat the process until the target value is found or the subarray is empty.

Linear regression is used for predicting continuous values, while logistic regression is used for predicting binary outcomes.

• Linear regression is used when the dependent variable is continuous and has a linear relationship with the independent variable.

• Logistic regression is used when the dependent variable is binary or categorical and the relationship is non-linear.

• Linear regression produces a straight line that best fits the data points, while logistic regression produces a...read more

The 'is' keyword is used for identity comparison, while '==' is used for equality comparison.

• The 'is' keyword checks if two objects are the same instance in memory.

• The '==' operator checks if two objects have the same value.

• Example: x is y (checks if x and y refer to the same object), x == y (checks if the values of x and y are equal)

List is mutable, Tuple is immutable in Python.

• List can be modified after creation, Tuple cannot be modified.

• List uses square brackets [], Tuple uses parentheses ().

• List is used for homogeneous data, Tuple is used for heterogeneous data.

Yes, I have prior knowledge of SQL.

• I have studied SQL as part of my computer science curriculum.

• I have also worked on projects where I used SQL to query and manipulate databases.

• I am familiar with writing SQL statements to retrieve data, create tables, and perform various database operations.

• I have experience with popular database management systems like MySQL and PostgreSQL.

Web API is a framework for building HTTP services that can be consumed by a broad range of clients.

• Web API is a part of ASP.NET framework.

• It is used to build RESTful services.

• It supports HTTP verbs like GET, POST, PUT, DELETE, etc.

• It can return data in various formats like JSON, XML, etc.

• It can be consumed by various clients like web browsers, mobile apps, etc.

A queue can be designed using an array or linked list data structure.

• A queue follows the FIFO (First In First Out) principle.

• Elements are added to the rear end and removed from the front end.

• Array implementation requires keeping track of front and rear indices.

• Linked list implementation requires keeping track of only front and rear nodes.

SQL joining query between two tables

• Use JOIN keyword to combine rows from two or more tables based on a related column between them

• Types of joins include INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN

• Example: SELECT * FROM table1 INNER JOIN table2 ON table1.column = table2.column

Overriding is when a subclass provides a specific implementation of a method that is already provided by its parent class. Overloading is when multiple methods have the same name but different parameters.

• Overriding: Subclass provides specific implementation of a method from parent class. Example: Animal class has a method 'sound', Cat class overrides it with 'meow'.

• Overloading: Multiple methods with same name but different parameters. Example: calculateArea(int side), calcula...read more

I am proficient in C and Java programming languages.

• Experience in developing applications using C and Java

• Knowledge of data structures and algorithms

• Familiarity with object-oriented programming concepts

• Ability to write efficient and optimized code

• Examples: Developed a Java-based web application for online shopping, Implemented a C program for sorting algorithms

Debugging in Python involves identifying and fixing errors in the code to ensure it runs correctly.

• Use print() statements to check the values of variables at different points in the code

• Utilize the built-in debugger pdb for more complex debugging tasks

• Check for syntax errors, logical errors, and runtime errors

• Use try-except blocks to catch and handle exceptions

• Consider using logging to track the flow of the program and identify issues

Print 'Hello, World!' in Python

• Use the print() function to display text on the screen

• Enclose the text in single or double quotes

ArrayList is a dynamic array that can grow or shrink in size, while LinkedList is a data structure where each element is a separate object with a reference to the next element.

• ArrayList uses a fixed-size array to store elements, while LinkedList uses nodes with references to the next node.

• ArrayList is faster for accessing elements by index, while LinkedList is faster for adding or removing elements in the middle of the list.

• Example: ArrayList - [1, 2, 3, 4], LinkedList - (1) ...read more

C++ code given to write output

• Understand the input and expected output

• Use cout to print output to console

• Handle errors and edge cases

Java is a high-level, object-oriented programming language used to develop applications for various platforms.

• Java is platform-independent and can run on any device with a Java Virtual Machine (JVM)

• It is known for its security features and is commonly used for developing web and mobile applications

• Java code is compiled into bytecode which can be executed on any platform

• Popular frameworks and libraries for Java include Spring, Hibernate, and Apache Struts

Polymorphism is the ability of an object to take on many forms.

• It allows objects of different classes to be treated as if they were objects of the same class.

• It is achieved through method overloading and method overriding.

• Example: A shape class can have different subclasses like circle, square, triangle, etc. and all can be treated as shapes.

• Example: A method can take different types of objects as parameters and perform different actions based on the object type.

JSON is used in ASP.NET for data exchange between client and server.

• Use Newtonsoft.Json NuGet package for JSON serialization and deserialization.

• Create a class with properties matching the JSON data structure.

• Use JsonConvert.SerializeObject() to convert object to JSON string.

• Use JsonConvert.DeserializeObject() to convert JSON string to object.

&& is a logical AND operator in JavaScript, while &&& is not a valid operator.

• && is used to combine two logical expressions and returns true only if both expressions are true

• &&& is not a valid operator in JavaScript and will result in a syntax error

DBMS features include data storage, retrieval, security, concurrency control, and data integrity.

• Data storage: DBMS allows for efficient storage and retrieval of data.

• Data retrieval: Users can easily query and retrieve specific data from the database.

• Security: DBMS provides mechanisms to control access to data and ensure data privacy.

• Concurrency control: DBMS manages multiple users accessing the database simultaneously.

• Data integrity: DBMS enforces rules to maintain the accur...read more

I'm sorry, but the question seems to be gibberish and does not make sense.

• The question appears to be a random string of letters with no discernible meaning.

• It is unclear what the interviewer is trying to ask or test for with this question.

• It may be best to ask for clarification or further explanation from the interviewer.

Object-oriented programming concepts like inheritance, polymorphism, encapsulation, and abstraction.

• Inheritance: Allows a class to inherit properties and behavior from another class.

• Polymorphism: Ability to present the same interface for different data types.

• Encapsulation: Bundling of data with the methods that operate on that data.

• Abstraction: Hiding the complex implementation details and showing only the necessary features.

OOPs concepts in Core Java

• Abstraction, Encapsulation, Inheritance, Polymorphism are the four pillars of OOPs in Java

• Abstraction is the process of hiding implementation details and showing only functionality

• Encapsulation is the process of binding data and methods together in a single unit

• Inheritance is the process of acquiring properties and behavior of a parent class by a child class

• Polymorphism is the ability of an object to take on many forms

• Interfaces and abstract classes ...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 problems

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

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

Knapsack problem involves maximizing the value of items in a knapsack without exceeding its weight limit. DFS is a graph traversal algorithm.

• Knapsack problem can be solved using dynamic programming approach.

• DFS (Depth First Search) is a graph traversal algorithm that explores as far as possible along each branch before backtracking.

• Example: In a knapsack problem, given items with weights and values, DFS can be used to explore all possible combinations of items to maximize val...read more

Java is a high-level programming language known for its portability, security, and versatility.

• Java is an object-oriented language

• It is platform-independent, meaning code can run on any device with a Java Virtual Machine (JVM)

• Java is used for developing a wide range of applications, from mobile apps to enterprise systems

String manipulation in Java involves operations like concatenation, substring, and comparison.

• Use the concat() method to concatenate two strings.

• Use the substring() method to extract a portion of a string.

• Use the equals() method to compare two strings for equality.

Arrays and lists in Python are data structures used to store multiple values in a single variable.

• Arrays in Python are created using the array module or numpy library.

• Lists in Python are created using square brackets [] and can store different data types.

• Arrays are more efficient for numerical operations, while lists are more flexible for general use.

• Example: array.array('i', [1, 2, 3]) or list = [1, 'hello', 3.14]

SQL commands for database manipulation

• SELECT * FROM table_name;

• INSERT INTO table_name (column1, column2) VALUES (value1, value2);

• UPDATE table_name SET column1 = value1 WHERE condition;

• DELETE FROM table_name WHERE condition;

Data structure implementation in Python

• Use built-in data structures like lists, dictionaries, sets, etc.

• Implement custom data structures like linked lists, stacks, queues, trees, etc.

• Utilize libraries like NumPy for efficient array operations

• Practice implementing algorithms using data structures

Healthcare automation involves using technology to streamline processes and improve efficiency in the medical field.

• Implementing electronic health records (EHR) systems to digitize patient information

• Utilizing telemedicine for remote consultations and monitoring

• Automating appointment scheduling and reminders

• Integrating AI algorithms for medical imaging analysis

• Developing mobile apps for patient engagement and monitoring

My B.Tech final project was an Android app for online grocery shopping.

• Developed using Java and Android Studio

• Integrated with payment gateway and Google Maps API

• Implemented user authentication and order tracking

• Conducted user testing and received positive feedback

• Received an A grade for the project

Pillars of OOPs include Encapsulation, Inheritance, Polymorphism, and Abstraction.

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

• Inheritance: Ability of a class to inherit properties and behavior from another class.

• Polymorphism: Ability to present the same interface for different data types.

• Abstraction: Hiding the complex implementation details and showing only the necessary features.