karsevar / Code_Challenge_Practice

This repository contains all of my completed HackerRank and Leetcode challenge answers with a couple of unittests.

Repository Documentation

1️⃣ Repository Summary

The following repository 'Code_Challenge_Practice' is the culmination of all the Leetcode and HackerRank problems that I have attempted and hopefully completed. Each problem within the repository is complete with their respective title (as documentated in the code challenge platform), the code challenge url, the difficulty (as documented in the code challenge platform) ranging from easy to hard, and my solution's time and space complexity calculation in Big O notation.

Each challenge is separated in their own individual files complete with the solution code (either written in Python and JavaScript), test files (if complicable to the challenge), and challenge specific readme.md file (which includes the rationale behind my solution, a more indepth analysis of the space and time complexity of the solution, and what specific places can be improved if one where to attempt the challenge a second time).

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Technologies Used

• Python and JavaScript (specific to the problem or which language I wanted to use to solve the problem).
• unittest and jest testing libraries for solutions written in Python and JavaScript respectively.

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2️⃣ Challenges (HackerRank and Leetcode)

Challenges Table

Title	Challenge URL	Time Complexity	Space Complexity	Difficulty
Binary Search Tree: Insertion	https://www.hackerrank.com/challenges/binary-search-tree-insertion/problem	O(n)	O(1)	Easy
Tree: Huffman Decoding	https://www.hackerrank.com/challenges/tree-huffman-decoding/problem	O(n)	O(n)	Medium
Tree: Top View	https://www.hackerrank.com/challenges/tree-top-view/problem	O(n)	O(n)	Easy
Reverse a doubly linked list	https://www.hackerrank.com/challenges/reverse-a-doubly-linked-list/problem	O(n)	O(n) Perhaps because of the call stack	Easy
Binary Search Tree: Lowest Common Ancestor	https://www.hackerrank.com/challenges/binary-search-tree-lowest-common-ancestor/problem	O(n)	O(n)	Easy
Is This a Binary Search Tree	https://www.hackerrank.com/challenges/is-binary-search-tree/problem	O(n)	O(n)	Medium
Maximum Element	https://www.hackerrank.com/challenges/maximum-element/problem	O(n)	O(n)	Easy
Queues: A Tale of Two Stacks	https://www.hackerrank.com/challenges/ctci-queue-using-two-stacks/problem	O(n)	O(n + m)	Medium
Inserting a Node into a Sorted Doubly Linked List	https://www.hackerrank.com/challenges/insert-a-node-into-a-sorted-doubly-linked-list/problem	O(n)	O(1)	Easy
Balanced Brackets	https://www.hackerrank.com/challenges/balanced-brackets/problem	O(n)	O(n)	Medium
Plus Minus	https://www.hackerrank.com/challenges/plus-minus/problem	O(n)	O(1)	Easy
Swap Nodes Algo	https://www.hackerrank.com/challenges/swap-nodes-algo/problem	O(nm)	O(n)	Medium
Equal Stacks	https://www.hackerrank.com/challenges/equal-stacks/problem	O(n)	O(1)	Easy
Game of Two Stacks	https://www.hackerrank.com/challenges/game-of-two-stacks/problem	O(n)	O(n)	Medium
Linked List Cycle II	https://leetcode.com/problems/linked-list-cycle-ii/	O(n)	O(1)	Medium
Palindrome Linked List	https://leetcode.com/problems/palindrome-linked-list/	O(n)	O(log(n))	Easy
Grid Search	https://www.hackerrank.com/challenges/the-grid-search/problem	O(n + m)	O(1)	Medium
Forming a Magic Square	https://www.hackerrank.com/challenges/magic-square-forming/problem	O(n^9)	O(1)	Medium

3️⃣ Contact Information

For anyone who has any questions about the above code challenges or wants share a better solution please contact me at [e-mail].