10+ Infosys Software Developer Interview Questions and Answers for Freshers

Find the maximum sum of a contiguous subarray in an array of integers.

• Use Kadane's algorithm to find the maximum subarray sum in linear time.

• Initialize two variables: maxEndingHere and maxSoFar to keep track of the current subarray sum and the maximum subarray sum seen so far.

• Iterate through the array and update the variables accordingly.

• Return the maxSoFar as the result.

Find the node where two linked lists merge, return -1 if no merging occurs.

• Traverse both lists to find their lengths and the difference in lengths

• Move the pointer of the longer list by the difference in lengths

• Traverse both lists simultaneously until they meet at the merging point

Count the number of unival sub-trees in a binary tree where all nodes below the root have the same value as the root node.

• Traverse the binary tree recursively and check if each subtree is a unival tree by comparing values with the root node.

• Keep track of the count of unival trees while traversing the tree.

• Return the total count of unival trees at the end of traversal.

Implement a program to compress a string by replacing consecutive duplicates with the count of repetitions.

• Iterate through the string and keep track of consecutive characters and their counts.

• Replace consecutive duplicates with the count of repetitions.

• Ensure the count of repetitions is ≤ 9.

• Return the compressed string.

Python is a high-level, interpreted programming language. Java is a compiled language.

• Python is dynamically typed while Java is statically typed

• Python has simpler syntax and is easier to learn than Java

• Java is faster and more efficient than Python

• Python is better suited for data analysis and machine learning while Java is better for enterprise applications

• Python has a larger community and more libraries than Java

OOP stands for Object-Oriented Programming. It is a programming paradigm based on the concept of objects.

• OOP is a way of organizing and designing code around objects

• It emphasizes encapsulation, inheritance, and polymorphism

• Encapsulation is the practice of hiding data and methods within an object

• Inheritance allows objects to inherit properties and methods from a parent object

• Polymorphism allows objects to take on multiple forms or behaviors

• Examples of OOP languages include Jav...read more

Sorting data in SQL queries

• Use ORDER BY clause to sort data in ascending or descending order

• Specify the column name to sort by

• Can sort by multiple columns

• Can use functions like COUNT, AVG, etc. in ORDER BY clause

• Example: SELECT * FROM table_name ORDER BY column_name ASC/DESC

• Example: SELECT * FROM table_name ORDER BY column1 ASC, column2 DESC

Python is interpreted and easy due to its dynamic nature and simple syntax.

• Python code is executed line by line, making it easy to debug and test.

• Python has a simple syntax that is easy to read and write.

• Python is dynamically typed, meaning that variables can change types during runtime.

• Python has a large standard library and many third-party modules, making it easy to accomplish complex tasks.

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

The main method syntax is a standard entry point for Java programs.

• The main method must be declared as public, static, and void.

• The method name must be 'main'.

• The method must accept an array of strings as an argument.

• The method must be defined within a class.

• Example: public static void main(String[] args) { }

Abstract class is a class that cannot be instantiated, List is a collection of objects, SQL is a language used to manage databases, ADO.net is a framework for accessing databases.

• Abstract class is used as a base class for other classes

• List is a generic collection of objects

• SQL is used to create, modify, and query databases

• ADO.net provides a set of classes for accessing databases

• Example: abstract class Animal { public abstract void MakeSound(); }

• Example: List names = new List(...read more

To check Java version, use command prompt/terminal and type 'java -version'.

• Open command prompt/terminal

• Type 'java -version'

• Press enter

• The installed Java version will be displayed

Unit testing is a software testing technique where individual units or components of a software are tested in isolation.

• Unit testing helps in identifying bugs early in the development process.

• It ensures that each unit of the software performs as expected.

• Common unit testing tools include JUnit, NUnit, PHPUnit, and MSTest.

Java is independent because of its platform-independent nature.

• Java code is compiled into bytecode which can run on any platform with a JVM installed.

• This allows Java to be used on multiple operating systems without any changes to the code.

• Java's platform independence is achieved through the use of the Java Virtual Machine (JVM).

Python is a high-level, interpreted programming language. Java is a general-purpose, class-based, object-oriented programming language.

• Python was created by Guido van Rossum in the late 1980s and released in 1991.

• Java was developed by James Gosling and his team at Sun Microsystems in the mid-1990s.

• Python is known for its simplicity, readability, and ease of use.

• Java is known for its platform independence, security, and scalability.

• Python is widely used in web development, sci...read more

HTML stands for Hypertext Markup Language, used for creating and structuring web pages.

• HTML is a markup language used to create the structure of web pages

• It consists of elements enclosed in tags, such as <html>, <head>, <body>

• Attributes can be added to elements to provide additional information or functionality, like <img src='image.jpg'>

The question is unclear and lacks context.

• Please provide more information or context for me to answer the question.

• Without additional information, I cannot provide a meaningful answer.

An end tag is used to mark the end of an HTML element.

• It is written as

• It is used to close an opening tag

• It is important for proper HTML syntax and rendering