20+ Cognizant Software Engineer Interview Questions and Answers for Freshers

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.

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.

Interview questions for Software Engineer position

• Datatypes: int, float, string, boolean, etc.

• Predefined functions: print(), len(), range(), etc.

• List is linear while tree is hierarchical. Trees are preferred for faster search and insertion.

• Class is a blueprint while object is an instance of a class.

• Inheritance is a way to create a new class from an existing class while polymorphism is the ability of an object to take on many forms.

• Aptitude question on time may involve calcula...read more

Waterfall model has five phases: requirements, design, implementation, testing, and maintenance.

• Requirements phase: gathering and documenting requirements

• Design phase: creating a detailed design based on requirements

• Implementation phase: coding and integrating components

• Testing phase: verifying that the system meets requirements

• Maintenance phase: making changes and updates to the system

• Example: building a website using waterfall model

• Example: developing a software application...read more

8086 is an advanced version of 8085 with more features and capabilities.

• 8086 has a 16-bit data bus while 8085 has an 8-bit data bus.

• 8086 has more registers than 8085.

• 8086 has a higher clock speed than 8085.

• 8086 supports virtual memory while 8085 does not.

• 8086 has a more advanced instruction set than 8085.

• Example: 8086 can perform multiplication and division operations while 8085 cannot.

A variable is a container that holds a value. A structure is a collection of variables of different data types.

• Variables are declared with a data type and a name, and can be assigned a value.

• Structures are declared using the 'struct' keyword and can contain variables of different data types.

• Example code: int age = 25; struct person { char name[20]; int age; float height; };

• Variables and structures are fundamental concepts in programming and are used extensively in software de...read more

Sort and search an array in software engineering interview

• Use built-in sorting functions or implement your own sorting algorithm

• For searching, use linear search or binary search depending on the size of the array

• Consider the time complexity of the sorting and searching algorithms

• Ensure the code is efficient and handles edge cases properly

Java 8 introduced new features like lambda expressions, streams, and default methods compared to Java 7.

• Java 8 introduced lambda expressions for functional programming.

• Java 8 added streams API for processing collections in a functional style.

• Java 8 introduced default methods in interfaces to allow adding new methods to interfaces without breaking existing implementations.

• Java 8 included the new Date and Time API (java.time) to address the shortcomings of the old java.util.Dat...read more

Variables in HTML are used to store and manipulate data within a web page.

• Variables in HTML are typically used in conjunction with JavaScript to store and manipulate data.

• They are declared using the 'var' keyword.

• Variables can store various types of data such as strings, numbers, and booleans.

• Example: var name = 'John';

Design patterns are reusable solutions to common software problems in Java.

• Design patterns provide a standard way to solve common problems in software development.

• They help in creating flexible, reusable, and maintainable code.

• Examples of design patterns include Singleton, Factory, Observer, and Decorator.

• Design patterns can be categorized into three types: creational, structural, and behavioral.

Pin diagram of 8085 microprocessor

• 8085 has 40 pins in total

• Pins are grouped into 5 categories: power supply, address bus, data bus, control and status signals

• Pin 1 is the reset pin, Pin 40 is the Vcc pin

• Examples of control signals: RD, WR, ALE, INT, HOLD

• Examples of status signals: S0, S1, IO/M, HLDA

Opamp stands for operational amplifier. It is an electronic device used to amplify and process signals.

• Opamps have high gain and can amplify signals to a very high degree.

• They are commonly used in audio amplifiers, filters, and signal processing circuits.

• Opamps have two input terminals and one output terminal.

• They can be configured in different ways to perform various functions such as amplification, filtering, and oscillation.

• Examples of opamps include LM741, LM358, and TL08...read more

A stack is a data structure that follows the Last In First Out (LIFO) principle.

• Elements are added to the top of the stack and removed from the top.

• Common operations include push (add element) and pop (remove element).

• Stacks are used in programming for function calls, expression evaluation, and memory management.

Inheritance is a mechanism in object-oriented programming where a new class is created by inheriting properties of an existing class.

• Inheritance allows code reusability and saves time and effort in writing new code.

• The existing class is called the parent or base class, and the new class is called the child or derived class.

• The child class inherits all the properties and methods of the parent class and can also add its own unique properties and methods.

• For example, a class 'An...read more

An array is a collection of elements of the same data type, stored in contiguous memory locations.

• Arrays can be one-dimensional or multi-dimensional

• Elements in an array can be accessed using their index

• Arrays can be initialized with values at declaration

• Examples: int[] numbers = {1, 2, 3}; char[] letters = {'a', 'b', 'c'};

• Arrays have a fixed size once declared

Data type in C refers to the type of data that a variable can hold.

• C has basic data types like int, float, char, double, etc.

• Derived data types like arrays, pointers, structures, and unions can also be created.

• Each data type has a specific range of values that it can hold.

• Data types can be modified using type qualifiers like const, volatile, etc.

Code to remove duplicate entries in a string

• Create an empty array to store unique strings

• Iterate through each string in the input array

• Check if the string is already in the unique array, if not add it

Synchronization in Java is the process of controlling access to shared resources by multiple threads.

• Synchronization is achieved using the synchronized keyword in Java.

• It ensures that only one thread can access the shared resource at a time.

• Synchronization can be applied to methods or blocks of code.

• It is used to prevent race conditions and ensure thread safety.

• Example: synchronized void myMethod() { //code }

• Example: synchronized(this) { //code }

Types of testing include unit, integration, system, acceptance, regression, performance, and security testing.

• Unit testing: testing individual units or components of the software

• Integration testing: testing how different units or components work together

• System testing: testing the entire system as a whole

• Acceptance testing: testing to ensure the software meets the requirements and is ready for release

• Regression testing: testing to ensure changes or updates to the software do ...read more

Program to reverse a given string.

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

• Use built-in functions like reverse() or slice() in some programming languages.

• Convert the string to an array, reverse the array, and then join the array back into a string.

Gibbs free energy is a thermodynamic potential that measures the maximum amount of work that can be obtained from a system.

• It is denoted by the symbol G.

• It takes into account both the enthalpy and entropy of a system.

• A negative value of G indicates that a reaction is spontaneous.

• It is used to predict the feasibility of a chemical reaction.

• It is also used in the study of phase transitions and the stability of materials.

A program using recursion

• Recursion is a technique where a function calls itself to solve a problem

• It involves a base case and a recursive case

• Examples include factorial, Fibonacci sequence, and binary search

A class is a blueprint for creating objects that have similar attributes and methods.

• A class is a user-defined data type that encapsulates data and functions.

• It is a template for creating objects.

• It provides a way to organize and structure code.

• Objects are instances of a class.

• Classes can inherit properties and methods from other classes.

• Examples include String, Integer, and List in Java.