HackerRank Interview Preparation Kit
January 19, 2021 · View on GitHub
This repository contains solutions to the Interview Preparation Kit Tutorial on HackerRank. My HackerRank profile can be viewed here.
To Contribute have a look at CONTRIBUTING.md and happy coding 😀 🐱💻
Sub Domains & Problems (+Solutions) in the Interview Preparation Kit
Warm Up Challenges 
| Problem | Difficulty | Solution Link |
|---|---|---|
| Sock Merchant | Easy |   |
| Counting Valleys | Easy | |
| Jumping on the clouds | Easy | |
| Repeated String | Easy | |
Arrays 
| Problem | Difficulty | Solution Link |
|---|---|---|
| Arrays Left Rotation | Easy | |
| 2D Array - DS | Easy | |
| New Year Chaos | Easy | |
| Minimum Swaps 2 | Medium | |
| Array Manipulation | Hard | |
String Manipulation
| Problem | Difficulty | Solution Link |
|---|---|---|
| Strings: Making Anagrams | Easy | |
| Alternating Characters | Easy | |
| Sherlock and The Valid String | Medium | |
| Special String Again | Medium | |
| Common Child | Medium | |
Search 
| Problem | Difficulty | Solution Link |
|---|---|---|
| Swap Nodes [Algo] | Medium | |
| Pairs | Medium | |
| Triple Sum | Medium | |
| Minimum Time Required | Medium |  |
| Hash Tables: Ice Cream Parlour | Medium | |
| Maximum Subarray Sum | Hard | |
| Making Candies | Hard |
Dictionaries and Hashmaps
| Problem | Difficulty | Solution Link |
|---|---|---|
| Hash Tables: Ransom Note | Easy | |
| Two Strings | Easy | |
| Sherlock and Anagrams | Medium | |
| Count Triplets | Medium | |
| Frequency Queries | Medium | |
Graphs
| Problem | Difficulty | Solution Link |
|---|---|---|
| Roads and Libraries | Medium | |
| Find The Nearest Clone | Medium | |
| BFS: Shortest Reach in Graph | Hard | |
| DFS Connected Cells In a Grid | Hard | |
| Matrix | Hard | |
Sorting 
| Problem | Difficulty | Solution Link |
|---|---|---|
| Sorting: Bubble Sort | Easy | |
| Mark and Toys | Easy | |
| Sorting: Comparator | Medium | |
| Fraudulent Activity Notification | Medium | |
| Merge Sort: Counting Inversions | Hard |
Greedy Algorithms
| Problem | Difficulty | Solution Link |
|---|---|---|
| Minimum Absolute Difference in an Array | Easy | |
| Luck Balance | Easy | |
| Greedy Florist | Medium | |
| Max Min | Medium | |
| Reverse Shuffle Merge | Advanced |
Dynamic Programming 
| Problem | Difficulty | Solution Link |
|---|---|---|
| Max Array Sum | Medium | |
| Abbreviation | Medium | |
| Candies | Medium | |
| Decibinary Numbers | Hard |
Stacks and Queues 
| Problem | Difficulty | Solution Link |
|---|---|---|
| Queues: A Tale of 2 Stacks | Medium | |
| Balanced Brackets | Medium | |
| Largest Rectangle | Medium | |
| Min Max Riddle | Medium | |
| Castle On The Grid | Medium | |
| Poisonous Plants | Hard |
Trees
| Problem | Difficulty | Solution Link |
|---|---|---|
| Tree: Height of Binary Tree | Easy | |
| Binary Search Tree: Lowest Common Ancestor | Easy | |
| Tree: Huffman Decoding | Medium | |
| Trees: Is This Binary Search Tree? | Medium | |
| Balanced Forest | Hard |
Linked Lists
| Problem | Difficulty | Solution Link |
|---|---|---|
| Linked Lists: Detect a Cycle | Easy | |
| Insert A Node at Specific Position In a Linked List | Easy | |
| Inserting a Node into a Sorted Doubly Linked List | Easy | |
| Reverse A Doubly Linked List | Easy | |
| Find Merge Points of Two Lists | Easy |
Recursion and Backtracking
| Problem | Difficulty | Solution Link |
|---|---|---|
| Recursion: Fibonacci Numbers | Easy | |
| Recursion: Davis' Staircase | Medium | |
| Crossword Puzzle | Medium | |
| Recursive Digit Sum | Medium |
Miscellaneous
| Problem | Difficulty | Solution Link |
|---|---|---|
| Flipping Bits | Easy | |
| Time Complexity: Primality | Medium | |
| Friend Circle Queries | Medium | |
| Maximum XOR | Medium |