10+ TCS Interview Questions and Answers

Offer competitive prices, provide excellent customer service, and diversify revenue streams.

• Offer competitive prices to attract more customers

• Provide excellent customer service to build customer loyalty

• Diversify revenue streams by offering additional services like car wash or convenience store

• Implement loyalty programs to incentivize repeat business

• Invest in technology to streamline operations and reduce costs

Find the most occuring element in array of strings

• Iterate through the array and count the occurrences of each element

• Keep track of the element with the highest count

• Return the element with the highest count

A Payment Management System can be designed using the four pillars of object-oriented programming: encapsulation, inheritance, polymorphism, and abstraction.

• Encapsulation: Hide the internal implementation details of payment processing and provide a public interface for interacting with the system.

• Inheritance: Create a hierarchy of payment classes such as CreditCardPayment, PayPalPayment, etc. to reuse common functionality.

• Polymorphism: Implement different payment methods usin...read more

SQL uses primary keys to uniquely identify records in a table, while NoSQL databases use unique keys for the same purpose.

• SQL databases use primary keys to uniquely identify each record in a table, typically using an auto-incrementing integer value.

• NoSQL databases use unique keys to achieve the same purpose, but the key can be any unique value, not necessarily an integer.

• In SQL, primary keys are used to enforce entity integrity and ensure data consistency, while in NoSQL, uni...read more

Implementing design using hashmap for efficient key-value storage and retrieval.

• Create a hashmap object to store key-value pairs.

• Use put() method to add key-value pairs to the hashmap.

• Use get() method to retrieve values based on keys.

• Handle collisions using chaining or open addressing techniques.

• Consider resizing the hashmap if load factor exceeds a certain threshold.

Encapsulation, Inheritance, Polymorphism, 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

Common puzzles found on GeeksforGeeks

• Tower of Hanoi

• N-Queens Problem

• Knights Tour Problem

• Sudoku Solver

• Water Jug Problem

Time complexity of binary tree refers to the amount of time it takes to perform operations on the tree based on its size.

• Time complexity for searching, inserting, and deleting in a binary tree is O(log n) on average.

• In worst case scenarios, time complexity can be O(n) for operations like searching if the tree is unbalanced.

• Balanced binary trees like AVL trees or Red-Black trees ensure O(log n) time complexity for all operations.

Implement stack using linked list

• Create a Node class with data and next pointer

• Create a Stack class with top pointer

• Implement push, pop, and peek methods by manipulating the linked list

Reverse a linked list by changing the direction of pointers

• Start with three pointers: current, previous, and next

• Iterate through the linked list, updating pointers to reverse the direction

• Update the head of the linked list to be the previous node