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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

Find whether a given array is a subset of another array

We are given two arrays, arr1 and arr2, that contains n, m number of distinct elements in unsorted order. We are supposed to...

Find all triplets such that sum of two equals to third element

We are given an array of n distinct integers and we have to find all triplets (3 elements), such that the sum of...

DP – Coin Change: Find number of ways of representing n cents

Given an infinite supply of 25 cents, 10 cents, 5 cents, and 1 cent. Find the number of ways of representing n cents....

Rotate a matrix by 90 degrees in the clockwise direction

We are given an NxN matrix and we have to rotate it by 90 degrees in a clockwise direction without using any extra space. Input: 10 11...

Rabin-Karp Algorithm for String Searching & Pattern Matching

Rabin-Karp is a pattern-matching algorithm that works by calculating the hash of the pattern to be searched(say Length M) and the hash of...

What is Web Cache and how does it speed up your website?

Web Cache (a.k.a HTTP Cache) is temporary storage used for storing frequently accessed static data such as HTML, CSS, images, etc to reduce...