Curated List · Tech Interview Handbook
Grind 75 LeetCode: Curated Coding Interview Problems & Tracker
The 64 highest-signal coding interview problems curated by the Tech Interview Handbook team. Organized by pattern — complete the Grind 75 and cover every core algorithmic pattern tested at FAANG.
Grind 75 was created by Yangshun Tay (author of Tech Interview Handbook) as an improved alternative to Blind 75. This page organizes those problems by pattern with our own templates and complexity notes.
17
Easy
40
Medium
7
Hard
| Problem | Difficulty | Solution | Link | |
|---|---|---|---|---|
| Two Sum
#Array
#Hash Map | Easy | Solution | ||
| Best Time to Buy and Sell Stock
#Array
#Dynamic Programming | Easy | Solution | ||
| Insert Interval
#Array | Medium | Solution | ||
| 3Sum
#Array
#Two Pointers
#Sorting | Medium | Solution | ||
| Product of Array Except Self
#Array
#Prefix Product | Medium | Solution | ||
| Combination Sum
#Array
#Backtracking | Medium | Solution |
| Problem | Difficulty | Solution | Link | |
|---|---|---|---|---|
| Missing Number
#Array
#Math
#Bit Manipulation | Easy | Solution |
| Problem | Difficulty | Solution | Link | |
|---|---|---|---|---|
| Search in Rotated Sorted Array
#Array
#Binary Search | Medium | Solution | ||
| Time Based Key-Value Store
#Hash Map
#Binary Search
#Design | Medium | Solution |
| Problem | Difficulty | Solution | Link | |
|---|---|---|---|---|
| Climbing Stairs
#DP
#Math
#Memoization | Easy | Solution | ||
| Coin Change
#Array
#DP
#BFS | Medium | Solution | ||
| Longest Increasing Subsequence
#Array
#DP
#Binary Search | Medium | Solution | ||
| Partition Equal Subset Sum
#Array
#Dynamic Programming | Medium | Solution | ||
| Unique Paths
#Math
#DP
#Combinatorics | Medium | Solution | ||
| Longest Common Subsequence
#String
#DP | Medium | Solution |
| Problem | Difficulty | Solution | Link | |
|---|---|---|---|---|
| Number of Islands
#Array
#DFS
#BFS | Medium | Solution | ||
| Rotting Oranges
#Array
#BFS
#Matrix | Medium | Solution | ||
| Course Schedule
#Graph
#DFS
#BFS | Medium | Solution | ||
| Number of Connected Components in an Undirected Graph Premium
#Graph
#DFS
#Union Find | Medium | Solution | ||
| Pacific Atlantic Water Flow
#Graph
#DFS
#BFS | Medium | Solution |
| Problem | Difficulty | Solution | Link | |
|---|---|---|---|---|
| Ransom Note | Easy | Practice | ||
| Group Anagrams
#String
#Hash Map
#Sorting | Medium | Solution |
| Problem | Difficulty | Solution | Link | |
|---|---|---|---|---|
| Merge K Sorted Lists
#Linked List
#Heap
#Divide and Conquer | Hard | Solution | ||
| Top K Frequent Elements
#Array
#Hash Map
#Heap | Medium | Solution | ||
| Find Median from Data Stream
#Two Heaps
#Design
#Sorting | Hard | Solution | ||
| Task Scheduler
#Array
#Heap
#Greedy | Medium | Solution |
| Problem | Difficulty | Solution | Link | |
|---|---|---|---|---|
| Non-overlapping Intervals
#Array
#Greedy
#Dynamic Programming | Medium | Solution | ||
| Meeting Rooms Premium
#Array
#Sorting | Easy | Solution |
| Problem | Difficulty | Solution | Link | |
|---|---|---|---|---|
| Reverse Linked List
#Linked List
#Recursion | Easy | Solution | ||
| Merge Two Sorted Lists
#Linked List
#Recursion | Easy | Solution | ||
| Linked List Cycle
#Linked List
#Two Pointers
#Hash Table | Easy | Solution | ||
| Middle of the Linked List | Easy | Practice | ||
| Reorder List
#Linked List
#Two Pointers
#Stack | Medium | Solution |
| Problem | Difficulty | Solution | Link | |
|---|---|---|---|---|
| Spiral Matrix
#Array
#Matrix
#Simulation | Medium | Solution | ||
| Set Matrix Zeroes
#Array
#Matrix | Medium | Solution | ||
| Rotate Image
#Array
#Matrix
#Math | Medium | Solution |
| Problem | Difficulty | Solution | Link | |
|---|---|---|---|---|
| Implement Queue using Stacks
#Stack | Easy | Solution | ||
| Backspace String Compare | Easy | Practice |
| Problem | Difficulty | Solution | Link | |
|---|---|---|---|---|
| Permutations
#Array
#Backtracking | Medium | Solution | ||
| Subsets
#Array
#Backtracking
#Bit Manipulation | Medium | Solution | ||
| Letter Combinations of a Phone Number
#Hash Table
#String
#Backtracking | Medium | Solution |
| Problem | Difficulty | Solution | Link | |
|---|---|---|---|---|
| Valid Parentheses
#String
#Stack | Easy | Solution | ||
| Min Stack
#Stack
#Design | Medium | Solution | ||
| Evaluate Reverse Polish Notation
#Array
#Math
#Stack | Medium | Solution | ||
| Decode String
#String
#Stack
#Recursion | Medium | Solution | ||
| Daily Temperatures
#Array
#Stack
#Monotonic Stack | Medium | Solution | ||
| Trapping Rain Water
#Array
#Two Pointers
#Stack | Hard | Solution | ||
| Largest Rectangle in Histogram
#Array
#Stack
#Monotonic Stack | Hard | Solution |
| Problem | Difficulty | Solution | Link | |
|---|---|---|---|---|
| Valid Palindrome
#String
#Two Pointers | Easy | Solution | ||
| Longest Palindromic Substring
#String
#Dynamic Programming | Medium | Solution | ||
| Longest Substring Without Repeating Characters
#String
#Hash Map
#Sliding Window | Medium | Solution | ||
| Minimum Window Substring
#String
#Hash Map
#Sliding Window | Hard | Solution |
| Problem | Difficulty | Solution | Link | |
|---|---|---|---|---|
| Invert Binary Tree
#Tree
#DFS
#BFS | Easy | Solution | ||
| Maximum Depth of Binary Tree
#Tree
#DFS
#BFS | Easy | Solution | ||
| Lowest Common Ancestor of a Binary Search Tree
#Tree
#DFS
#BST | Easy | Solution | ||
| Binary Tree Level Order Traversal
#Tree
#BFS | Medium | Solution | ||
| Validate Binary Search Tree
#Tree
#DFS
#BST | Medium | Solution | ||
| Kth Smallest Element in a BST
#Tree
#DFS
#BST | Medium | Solution | ||
| Serialize and Deserialize Binary Tree
#Tree
#DFS
#BFS | Hard | Solution | ||
| Word Search
#Array
#Matrix
#Backtracking | Medium | Solution |
| Problem | Difficulty | Solution | Link | |
|---|---|---|---|---|
| Implement Trie (Prefix Tree)
#Design
#Trie | Medium | Solution | ||
| Word Break
#String
#DP
#Hash Set | Medium | Solution | ||
| Word Search II
#Array
#String
#Backtracking | Hard | Solution |
| Problem | Difficulty | Solution | Link | |
|---|---|---|---|---|
| Container With Most Water
#Array
#Two Pointers
#Greedy | Medium | Solution |
Want more curated resources?
Explore coding interview patterns with code templates, or check Blind 75 — the original community-curated list.
How is Grind 75 different from Blind 75?
Both lists target 75 problems, but they differ in origin, methodology, and coverage. Here's what you need to know before choosing which grind 75 vs blind 75 route to take.
Grind 75 (this list)
- • Created by Tech Interview Handbook team (Yangshun Tay)
- • Algorithm-selected for quality, not hand-curated
- • 17 pattern categories including Trie, Queue, Recursion
- • More modern — covers problem types added post-2020
- • Better balanced across difficulty levels
Blind 75
- • Anonymous list from the Blind job forum (2018)
- • Manually curated by an ex-Facebook engineer
- • 10 categories organized by data structure
- • The "industry standard" — widely referenced in guides
- • More overlap with LeetCode top 100 frequent
Bottom line: do both lists together for comprehensive coverage. Start with Blind 75 for the canonical experience, then fill gaps with Grind 75. Or use our pattern-based approach to learn the underlying templates first.
Frequently Asked Questions
What is Grind 75?
Grind 75 is a curated list of 75 LeetCode problems created by Yangshun Tay, author of Tech Interview Handbook. It uses a scoring algorithm based on problem quality, difficulty distribution, and pattern coverage — making it a smarter, data-driven alternative to Blind 75.
How long does it take to complete the Grind 75 list?
Most engineers complete the grind 75 problems in 3–6 weeks spending 1–2 hours per day. If you are new to algorithms, budget 6–8 weeks to learn patterns properly. The goal is pattern recognition, not memorization — rushing defeats the purpose.
Grind 75 vs NeetCode 150 — which is better?
Grind 75 is the right choice if you have 4–6 weeks. NeetCode 150 extends to 150 problems with deeper coverage of 2D DP, advanced graphs, and bit manipulation — better for 8–12 week timelines or roles at top-tier companies like Google. Both grind 75 and neetcode 150 are excellent; pick based on your time budget.
Should I do problems in order or by pattern?
Always solve by pattern, not by category order. Start with Arrays and Strings (foundation), then Two Pointers, Binary Search, and Hash Table. Move to Trees and BFS/DFS next, then Heap and Backtracking. Save Dynamic Programming for last — it builds on pattern intuition from simpler topics.
Are all Grind 75 problems free on LeetCode?
Most are free. A few problems (like Meeting Rooms and Number of Connected Components) are LeetCode Premium. These are marked with a star icon above. You can find free versions of premium problems on platforms like LintCode, NeetCode.io, or AlgoExpert.