Neetcode 150 and Blind 75

📘 Collection of 225 leetcode problems. Includes solutions and quizzes/questions/tests in flashcards format (Anki) to learn patterns/techniques.

Resources

• 🎁 New Year Gift - Curated List of Top 75 LeetCode Questions to Save Your Time
• 🚀 NeetCode
  • Practice
  • Roadmap
  • Algorithms and Data Structures for Beginners
  • Advanced Algorithms
• 🥇 Leetcode
  • Blind 75 list
  • Top interview 150
• 🧩 Leetcode patterns

Problems

#	Title	Solution	Time	Space	Difficulty
217	Contains Duplicate	Typescript	O(n)	O(n)	Easy
242	Valid Anagram	Typescript	O(n)	O(n)	Easy

Practice questions

Disclaimer: Some of the questions are taken from https://neetcode.io/practice, only the questions that correspond to the "free" category were used, the content belongs to neetcode and is only being used for educational purposes.

Contents

The questions in this section are designed to help you remember the patterns or techniques used throughout the problems. The problems are in a Q&A format, this is to facilitate the creation of a deck of Anki cards.

The order is based on the roadmap created by neetcode

✅ - Transcribed/created questions (may need revision)
📘 - Questions that need to be transcribed
⚠️ - Questions that do not appear on neetcode.io or are behind a paywall and need to be created

Arrays and Hashing

1. Contains Duplicate (Blind) ✅
2. Valid Anagram (Blind) ✅
3. Two Sum (Blind) ✅
4. Group Anagrams (Blind) ✅⚠
5. Top K Frequent Elements (Blind) ✅⚠
6. Product of Array Except Self (Blind) ⚠
7. Valid Sudoku ⚠
8. Encode and Decode Strings (Blind) ✅
9. Longest Consecutive Sequence (Blind) ✅

Two Pointers

1. Valid Palindrome (Blind) ✅
2. Two Sum II ⚠
3. 3Sum (Blind) ✅
4. Container With Most Water (Blind) ✅
5. Trapping Rain Water ⚠

Sliding Window

1. Best Time to Buy and Sell Stock (Blind) ✅
2. Longest Substring Without Repeating Characters (Blind) ✅
3. Longest Repeating Character Replacement (Blind) ✅
4. Permutation in String ⚠
5. Minimum Window Substring (Blind) ✅
6. Sliding Window Maximum ⚠

Stack

1. Valid Parentheses (Blind) ✅
2. Min Stack ⚠
3. Evaluate Reverse Polish Notation ⚠
4. Generate Parentheses ⚠
5. Daily Temperatures ⚠
6. Car Fleet ⚠
7. Largest Rectangle in Histogram ⚠

Binary Search

1. Binary Search ⚠
2. Search a 2D Matrix ⚠
3. Koko Eating Bananas ⚠
4. Search in Rotated Sorted Array (Blind) ✅
5. Find Minimum in Rotated Sorted Array (Blind) ✅
6. Time Based Key-Value Store ⚠
7. Median of Two Sorted Arrays ⚠

Linked List

1. Reverse Linked List (Blind) ✅
2. Merge Two Sorted Lists (Blind) ✅
3. Reorder List (Blind) ✅
4. Remove Nth Node From End of List (Blind) ✅
5. Copy List with Random Pointer ⚠
6. Add Two Numbers ⚠
7. Linked List Cycle (Blind) ⚠
8. Find the Duplicate Number ⚠
9. LRU Cache ⚠
10. Merge k Sorted Lists (Blind) ⚠
11. Reverse Nodes in k-Group ✅

Trees

1. Invert Binary Tree (Blind) ✅
2. Maximum Depth of Binary Tree (Blind) ✅
3. Diameter of Binary Tree ⚠
4. Balanced Binary Tree ⚠
5. Same Tree (Blind) 📘
6. Subtree of Another Tree (Blind) 📘
7. Lowest Common Ancestor of a Binary Search Tree (Blind) 📘
8. Binary Tree Level Order Traversal (Blind) 📘
9. Binary Tree Right Side View ⚠
10. Count Good Nodes in Binary Tree ⚠
11. Validate Binary Search Tree (Blind) ⚠
12. Kth Smallest Element in a BST (Blind) ⚠
13. Construct Binary Tree from Preorder and Inorder Traversal (Blind) ⚠
14. Binary Tree Maximum Path Sum (Blind) ⚠
15. Serialize and Deserialize Binary Tree (Blind) ⚠

Trie

1. Implement Trie (Blind) ⚠
2. Design Add and Search Words Data Structure (Blind) ⚠
3. Word Search II (Blind) ⚠

Heap and Priority Queue

1. Kth Largest Element in a Stream ⚠
2. Last Stone Weight ⚠
3. K Closest Points to Origin ⚠
4. Kth Largest Element in an Array ⚠
5. Task Scheduler ⚠
6. Design Twitter ⚠
7. Find Median from Data Stream (Blind) ⚠

Backtracking

1. Permutations ⚠
2. Sudoku Solver ⚠
3. Subsets ⚠
4. Combination Sum (Blind) 📘
5. Subsets II ⚠
6. Word Search (Blind) ⚠
7. Palindrome Partitioning ⚠
8. Letter Combinations of a Phone Number ⚠
9. N-Queens ⚠

Graphs

1. Number of Islands (Blind) 📘
2. Clone Graph (Blind) ⚠
3. Max Area of Island ⚠
4. Pacific Atlantic Water Flow (Blind) ⚠
5. Surrounded Regions ⚠
6. Rotting Oranges ⚠
7. Walls and Gates ⚠
8. Course Schedule (Blind) ⚠
9. Course Schedule II ⚠
10. Redundant Connection ⚠
11. Number of Connected Components In An Undirected Graph (Blind) ⚠
12. Graph Valid Tree (Blind) ⚠
13. Word Ladder ⚠

Advance Graphs

1. Reconstruct Itinerary ⚠