Blind75 Questions with Answers
The Blind 75 list is a curated list of 75 important coding
questions designed to help software engineers prepare for coding
interviews. The list was created by an ex-Meta Staff Engineer
and has become very popular in the coding interview scene
What is the Blind 75 list? The Blind 75 list is a compilation of 75 coding questions that are considered crucial for coding interviews. The list was curated by Yangshun Tay, who used it during his own job hunt to focus on the most important questions. The list was shared on Blind and LeetCode forums, where it gained popularity and was named "Blind 75"
Benefits of the Blind 75 list:
- Focused Practice: The list helps you focus on the most important questions, saving time and effort.
- Variety of Problems: The list covers a wide range of topics and problem types, providing comprehensive interview preparation.
- Preparation Schedule: The list is spread across different data structures and algorithmic techniques, helping you manage your preparation time effectively
- Real Interview Scenario: You are advised to treat the practice like a real coding interview, which helps in building the right mindset and approach for actual interviews..
How it can help engineers prepare for their coding interviews:
- Understanding Key Concepts: The list covers a variety of topics, helping engineers understand key concepts and algorithms.
- Improving Problem-Solving Skills: Regular practice with these questions can help improve problem-solving and coding skills.
- Building Confidence: By practicing with these important questions, engineers can build confidence for their coding interviews.
- Performance Tracking: The list can be used to track progress and identify areas that need more focus
Blind 75 Questions:
Here are the questions included in the Blind 75 list:
Sequences
Question | Difficulty | Practice | Solution |
|---|---|---|---|
| 1. Two Sum | Easy | Link | Link |
| 2. Contains Duplicate | Easy | Link | Link |
| 3. Best Time to Buy and Sell Stock | Easy | Link | Link |
| 4. Valid Anagram | Medium | Link | Link |
| 5. Valid Parentheses | Medium | Link | Link |
| 6. Maximum Subarray | Medium | Link | Link |
| 7. Product of Array Except Self | Medium | Link | Link |
| 8. 3Sum | Medium | Link | Link |
| 9. Merge Intervals | Medium | Link | Link |
| 10. Group Anagrams | Medium | Link | Link |
| 11. Maximum Product Subarray | Medium | Link | Link |
| 12. Search in Rotated Sorted Array | Medium | Link | Link |
Data structures
Question | Difficulty | Practice | Solution |
|---|---|---|---|
| 1. Reverse a Linked List | Easy | Link | Link |
| 2. Detect Cycle in a Linked List | Easy | Link | Link |
| 3. Container With Most Water | Medium | Link | Link |
| 4. Find Minimum in Rotated Sorted Array | Medium | Link | Link |
| 5. Longest Repeating Character Replacement | Medium | Link | Link |
| 6. Longest Substring Without Repeating Characters | Medium | Link | Link |
| 7. Number of Islands | Medium | Link | Link |
| 8. Remove Nth Node From End Of List | Medium | Link | Link |
| 9. Palindromic Substrings | Medium | Link | Link |
| 10. Pacific Atlantic Water Flow | Medium | Link | Link |
| 11. Minimum Window Substring | Medium | Link | Link |
Non-linear data structures
Question | Difficulty | Practice | Solution |
|---|---|---|---|
| 1. Invert/Flip Binary Tree | Easy | Link | Link |
| 2. Validate Binary Search Tree | Medium | Link | Link |
| 3. Non-overlapping Intervals | Medium | Link | Link |
| 4. Construct Binary Tree from Preorder and Inorder Traversal | Medium | Link | Link |
| 5. Top K Frequent Elements | Medium | Link | Link |
| 6. Clone Graph | Medium | Link | Link |
| 7. Task Schedule | Medium | Link | Link |
| 8. Serialize and Deserialize Binary Tree | Hard | Link | Link |
| 9. Binary Tree Maximum Path Sum | Hard | Link | Link |
| 10. Maximum Depth of Binary Tree | Easy | Link | Link |
| 11. Same Tree | Easy | Link | Link |
| 12. Binary Tree Level Order Traversal | Medium | Link | Link |
| 13. Encode and Decode Strings | Medium | Link | Link |
More data structures
Question | Difficulty | Practice | Solution |
|---|---|---|---|
| 1. Subtree of Another Tree | Easy | Link | Link |
| 2. Lowest Common Ancestor of BST | Medium | Link | Link |
| 3. Implement Trie (Prefix Tree) | Medium | Link | Link |
| 4. Add and Search Word | Medium | Link | Link |
| 5. Kth Smallest Element in a BST | Medium | Link | Link |
| 6. Merge K Sorted Lists | Hard | Link | Link |
| 7. Find Median from Data Stream | Hard | Link | Link |
| 8. Insert Interval | Medium | Link | Link |
| 9. Longest Consecutive Sequence | Medium | Link | Link |
| 10. Word Search II | Hard | Link | Link |
| 11. Meeting Rooms | Easy | Link | Link |
| 12. Meeting Rooms II | Medium | Link | Link |
| 13. Graph Valid Tree | Medium | Link | Link |
| 14. Number of Connected Components in an Undirected Graph | Medium | Link | Link |
| 15. Alien Dictionary | Hard | Link | Link |
Dynamic programming
Question | Difficulty | Practice | Solution |
|---|---|---|---|
| 1. Climbing Stairs | Easy | Link | Link |
| 2. Coin Change | Medium | Link | Link |
| 3. Longest Increasing Subsequence | Medium | Link | Link |
| 4. Combination Sum | Medium | Link | Link |
| 5. House Robber | Medium | Link | Link |
| 6. House Robber II | Medium | Link | Link |
| 7. Decode Ways | Medium | Link | Link |
| 8. Unique Paths | Medium | Link | Link |
| 9. Jump Game | Medium | Link | Link |
| 10. Word Break | Medium | Link | Link |
