My HackerRank Solutions

This repository contains my solutions for the challenges hosted @ HackerRank.com All problems are solved in Java. Each challenge contains the original problem statement in pdf format, testcases as well as my suggested solution.

Below is a list of the challenges currently hosted in this repository.

All Competitions

Project Euler+

Challenge	Problem Statement	Solution	Testcases
Project Euler #2: Even Fibonacci numbers	PDF	Java	zip
Project Euler #1: Multiples of 3 and 5	PDF	Java	zip

Practice

Cracking the Coding Interview

Challenge	Problem Statement	Solution	Testcases
Arrays: Left Rotation	PDF	Java	None
DFS: Connected Cell in a Grid	PDF	Java	zip
Recursion: Davis' Staircase	PDF	Java	zip
Recursion: Fibonacci Numbers	PDF	Java	zip
Sorting: Bubble Sort	PDF	Java	zip
Sorting: Comparator	PDF	Java	zip
Trees: Is This a Binary Search Tree?	PDF	Java	zip

Algorithms

Constructive Algorithms

Challenge	Problem Statement	Solution	Testcases
New Year Chaos	PDF	Java	zip

Greedy

Challenge	Problem Statement	Solution	Testcases
Mark and Toys	PDF	Java	zip

Implementation

Challenge	Problem Statement	Solution	Testcases
ACM ICPC Team	PDF	Java	zip
Angry Professor	PDF	Java	zip
Append and Delete	PDF	Java	zip
Apple and Orange	PDF	Java	zip
Beautiful Days at the Movies	PDF	Java	zip
Beautiful Triplets	PDF	Java	zip
Between Two Sets	PDF	Java	zip
Birthday Chocolate	PDF	Java	zip
Bon Appétit	PDF	Java	zip
Breaking the Records	PDF	Java	zip
Cats and a Mouse	PDF	Java	zip
Cavity Map	PDF	Java	zip
Chocolate Feast	PDF	Java	zip
Circular Array Rotation	PDF	Java	zip
Climbing the Leaderboard	PDF	Java	zip
Counting Valleys	PDF	Java	zip
Cut the sticks	PDF	Java	zip
Day of the Programmer	PDF	Java	zip
Designer PDF Viewer	PDF	Java	zip
Divisible Sum Pairs	PDF	Java	zip
Drawing Book	PDF	Java	zip
Electronics Shop	PDF	Java	zip
Equalize the Array	PDF	Java	zip
Extra Long Factorials	PDF	Java	zip
Fair Rations	PDF	Java	zip
Find Digits	PDF	Java	zip
Forming A Magic Square	PDF	Java	zip
Grading Students	PDF	Java	zip
Jumping on the Clouds	PDF	Java	zip
Jumping on the Clouds: Revisited	PDF	Java	zip
Kangaroo	PDF	Java	zip
Library Fine	PDF	Java	zip
Lisa's Workbook	PDF	Java	zip
Matrix Layer Rotation	PDF	Java	zip
Migratory Birds	PDF	Java	zip
Minimum Distances	PDF	Java	zip
Non-Divisible Subset	PDF	Java	zip
Picking Numbers	PDF	Java	zip
Repeated String	PDF	Java	zip
Save the Prisoner	PDF	Java	zip
Sequence Equation	PDF	Java	zip
Service Lane	PDF	Java	zip
Sherlock and Squares	PDF	Java	zip
Sock Merchant	PDF	Java	zip
Taum and B'day	PDF	Java	zip
The Hurdle Race	PDF	Java	zip
Utopian Tree	PDF	Java	zip
Viral Advertising	PDF	Java	zip

Warmup

Challenge	Problem Statement	Solution	Testcases
A Very Big Sum	PDF	Java	zip
Birthday Cake Candles	PDF	Java	zip
Compare the Triplets	PDF	Java	zip
Diagonal Difference	PDF	Java	zip
Mini-Max Sum	PDF	Java	zip
PlusMinus	PDF	Java	zip
Simple Array Sum	PDF	Java	zip
Solve Me First	PDF	Java	zip
Staircase	PDF	Java	zip
Time Conversion	PDF	Java	zip

Artificial Intelligence

A*Search

Challenge	Problem Statement	Solution	Testcases
PacMan - BFS	PDF	Java	zip
PacMan - DFS	PDF	Java	zip

Bot Building

Challenge	Problem Statement	Solution	Testcases
BotClean	PDF	Java	zip
BotClean Stochastic	PDF	Java	zip
Bot saves princess	PDF	Java	zip
Bot saves princess - 2	PDF	Java	zip

Data Structures

Arrays

Challenge	Problem Statement	Solution	Testcases
Array Manipulation	PDF	Java	zip
Array DS	PDF	Java	zip
Dynamic Array	PDF	Java	zip
Left Rotation	PDF	Java	zip
Sparse Arrays	PDF	Java	zip
2D Array DS	PDF	Java	zip

Heap

Challenge	Problem Statement	Solution	Testcases
Jesse and Cookies	PDF	Java	zip
QHEAP1	PDF	Java	zip

LinkedLists

Challenge	Problem Statement	Solution	Testcases
Compare Two Linked Lists	PDF	Java	zip
Cycle Detection	PDF	Java	zip
Delete A Node	PDF	Java	zip
Delete Duplicate-Value Nodes From a Sorted Linked List	PDF	Java	zip
Find Merge Point of Two Lists	PDF	Java	zip
Get Node Value	PDF	Java	zip
Insert a Node at a Specific Position in a Linked List	PDF	Java	zip
Insert a Node at the Head of a Linked List	PDF	Java	zip
Insert a Node at the Tail of a Linked List	PDF	Java	zip
Inserting a Node Into a Sorted Doubly Linked List	PDF	Java	zip
Merge Two Sorted Linked Lists	PDF	Java	zip
Print In Reverse	PDF	Java	zip
Print the Elements of a Linked List	PDF	Java	zip
Reverse a doubly linked list	PDF	Java	zip
Reverse a Linked List	PDF	Java	zip

Queues

Challenge	Problem Statement	Solution	Testcases
Queue Using Two Stacks	PDF	Java	zip

Stacks

Challenge	Problem Statement	Solution	Testcases
Balanced Brackets	PDF	Java	zip
Equal Stacks	PDF	Java	zip
Maximum Element	PDF	Java	zip

Trees

Challenge	Problem Statement	Solution	Testcases
Binary Search Tree : Insertion	PDF	Java	zip
Binary Search Tree : Lowest Common Ancestor	PDF	Java	zip
Swap Nodes [Algo]	PDF	Java	zip
Tree: Height of a Binary Tree	PDF	Java	zip
Tree: Huffman Decoding	PDF	Java	zip
Tree: Inorder Traversal	PDF	Java	zip
Tree: Level Order Traversal	PDF	Java	zip
Tree: Postorder Traversal	PDF	Java	zip
Tree: Preorder Traversal	PDF	Java	zip
Tree : Top View	PDF	Java	zip

Trie

Challenge	Problem Statement	Solution	Testcases
Contacts	PDF	Java	zip

Java

Challenge	Problem Statement	Solution	Testcases
Java Currency Formatter	PDF	Java	zip