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Data Structure

Learn most popular data structures and their implementation

System Design

Learn how to design system architecture that can scale million of users


Level up your coding skill by practising most popular programming question from various doamins.

Practice Coding Interview Problems

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Coin Change: Find number of ways of representing n cents

Dynamic Programming

Designing a scalable URL Shortener like Tiny URL

System Design - Nlogn

Reverse a linked list in Linear Time without using extra space

Linked List

Insert, Search and Delete Operation in Binary Search Tree

Tree Data Structure

Latest blog post at Nlogn

Array in C/CPP Programming Langauages with Example

An array in C or CPP is a collection of elements with similar data types stored in a contiguous memory location. The elements...

Find subarray with given sum (Non-negative Numbers)

Given a non-negative subarray of size n, we have to find the index of subarrays such that their sum is equal to the...

SQL vs NoSQL Databases

A database is an organized collection of data, generally stored and accessed from a computer system. There are two major types of databases available: SQL and...

Count the number of islands

Given a binary 2D matrix, containing the combination of 1's and 0's, where 0's represents the water and 1's represent the land. Our...

Call by value and call by reference in C++

There are two ways to pass arguments to a function in CPP: Call by Value or Call by Reference. The Call by Value...

What are Long Polling, WebSockets, and Server-Sent Events

Before understanding Long Polling, WebSockets, Server-Sent Events lets understand how the basic communication over the internet using HTTP request happens. HTTP is the...