CloudCollection 📚

A comprehensive collection of algorithm solutions, system design materials, and modern C++ tutorials. Perfect for interview preparation, learning, and reference.

🧮 Data Structures & Algorithms

Organized by topic and difficulty level, with detailed solutions and explanations.

📊 Array & Two Pointers

0001. Two Sum
0011. Container With Most Water
0015. 3Sum
0016. 3Sum Closest
0018. 4Sum
0027. Remove Element
0031. Next Permutation
0042. Trapping Rain Water
0045. Jump Game II
0055. Jump Game
0056. Merge Intervals
0057. Insert Interval
0066. Plus One
0075. Sort Colors
0088. Merge Sorted Array
0189. Rotate Array
0238. Product of Array Except Self
0283. Move Zeroes
0347. Top K Frequent Elements
0349. Intersection of Two Arrays
0350. Intersection of Two Arrays II
0605. Can Place Flowers
0724. Find Pivot Index
1010. Pairs of Songs With Total Durations Divisible by 60
1299. Replace Elements with Greatest Element on Right Side
1984. Minimum Difference Between Highest and Lowest of K Scores
Two Sum II - Input Array Is Sorted

📝 String

0003. Longest Substring Without Repeating Characters
0005. Longest Palindromic Substring
0006. Zigzag Conversion
0012. Integer to Roman
0013. Roman to Integer
0014. Longest Common Prefix
0020. Valid Parentheses
0028. Find the Index of the First Occurrence in a String
0038. Count and Say
0043. Multiply Strings
0058. Length of Last Word
0071. Simplify Path
0125. Valid Palindrome
0205. Isomorphic Strings
0242. Valid Anagram
0290. Word Pattern
0344. Reverse String
0392. Is Subsequence
0929. Unique Email Addresses
1209. Remove All Adjacent Duplicates in String II
Add Strings
Anagram Difference
Count Binary Substrings
Decode String
Expressive Words
Fraction to Recurring Decimal
Minimum Number of Steps to Make Two Strings Anagram
Reorganize String
Reverse Words in a String III
Verifying an Alien Dictionary
Word Break

🔗 Linked List

0002. Add Two Numbers
0019. Remove Nth Node From End of List
0021. Merge Two Sorted Lists
0024. Swap Nodes in Pairs
0025. Reverse Nodes in K-Group.md 0061. Rotate List
0083. Remove Duplicates from Sorted List
0092. Reverse Linked List II
0143. Reorder List
0160. Intersection of Two Linked Lists
0203. Remove Linked List Elements
0206. Reverse Linked List
0234. Palindrome Linked List
0876. Middle of the Linked List
Linked List Cycle
Linked List Cycle II

🌳 Tree

0094. Binary Tree Inorder Traversal
0098. Validate Binary Search Tree
0100. Same Tree
0101. Symmetric Tree
0102. Binary Tree Level Order Traversal
0103. Binary Tree Zigzag Level Order Traversal
0104. Maximum Depth of Binary Tree
0105. Construct Binary Tree from Preorder and Inorder Traversal
[0106. Construct Binary