Grind 75

Link: https://www.techinterviewhandbook.org/grind75?order=all_rounded

Week 1

#	Problem	Difficulty	Time	Topic
1.	Two Sum	Easy	15 mins	Array
2.	Valid Parentheses	Easy	20 mins	Stack
3.	Merge Two Sorted Lists	Easy	20 mins	Linked List
4.	Best Time to Buy and Sell Stock	Easy	20 mins	Array
5.	Valid Palindrome	Easy	15 mins	String
6.	Invert Binary Tree	Easy	15 mins	Binary Tree
7.	Valid Anagram	Easy	15 mins	String
8.	Binary Search	Easy	15 mins	Binary Search
9.	Flood Fill	Easy	20 mins	Graph
10.	Maximum Subarray	Medium	20 mins	Dynamic Programming
11.	Lowest Common Ancestor of a Binary Search Tree	Easy	20 mins	Binary Search Tree
12.	Insert Interval	Medium	25 mins	Array

Week 2

#	Problem	Difficulty	Time	Topic
1.	01 Matrix	Medium	30 mins	Graph
2.	K Closest Points to Origin	Medium	30 mins	Heap
3.	Balanced Binary Tree	Easy	15 mins	Binary Tree
4.	Linked List Cycle	Easy	20 mins	Linked List
5.	Implement Queue using Stacks	Easy	20 mins	Stack
6.	First Bad Version	Easy	20 mins	Binary Search
7.	Ransom Note	Easy	15 mins	Hash Table
8.	Longest Substring Without Repeating Characters	Medium	30 mins	String
9.	3Sum	Medium	30 mins	Array
10.	Binary Tree Level Order Traversal	Medium	20 mins	Binary Tree

Week 3

#	Problem	Difficulty	Time	Topic
1	Clone Graph	Medium	25 mins	Graph
2	Evaluate Reverse Polish Notation	Medium	30 mins	Stack
3	Course Schedule	Medium	30 mins	Graph
4	Implement Trie (Prefix Tree)	Medium	35 mins	Trie
5	Coin Change	Medium	25 mins	Dynamic Programming
6	Product of Array Except Self	Medium	30 mins	Array
7	Climbing Stairs	Easy	20 mins	Dynamic Programming
8	Longest Palindrome	Easy	20 mins	String
9	Min Stack	Medium	20 mins	Stack

Week 4

#	Problem	Difficulty	Time	Topic
1	Reverse Linked List	Easy	20 mins	Linked List
2	Validate Binary Search Tree	Medium	20 mins	Binary Search Tree
3	Number of Islands	Medium	25 mins	Graph
4	Rotting Oranges	Medium	30 mins	Graph
5	Search in Rotated Sorted Array	Medium	30 mins	Binary Search
6	Combination Sum	Medium	30 mins	Array
7	Permutations	Medium	30 mins	Recursion
8	Merge Intervals	Medium	30 mins	Array
9	Lowest Common Ancestor of a Binary Tree	Medium	25 mins	Binary Tree

Week 5

#	Problem	Difficulty	Time	Topic
1	Time Based Key-Value Store	Medium	35 mins	Binary Search
2	Minimum Window Substring	Hard	30 mins	String
3	Serialize and Deserialize Binary Tree	Hard	40 mins	Binary Tree
4	Trapping Rain Water	Hard	35 mins	Stack
5	Find Median from Data Stream	Hard	30 mins	Heap
6	Majority Element	Easy	20 mins	Array
7	Add Binary	Easy	15 mins	Binary
8	Diameter of Binary Tree	Easy	30 mins	Binary Tree

Week 6

#	Problem	Difficulty	Time	Topic
1	Middle of the Linked List	Easy	20 mins	Linked List
2	Accounts Merge	Medium	30 mins	Graph
3	Sort Colors	Medium	25 mins	Array
4	Word Break	Medium	30 mins	Trie
5	Partition Equal Subset Sum	Medium	30 mins	Dynamic Programming
6	String to Integer (atoi)	Medium	25 mins	String
7	Spiral Matrix	Medium	25 mins	Matrix
8	Subsets	Medium	30 mins	Recursion
9	Binary Tree Right Side View	Medium	20 mins	Binary Tree

Week 7

#	Problem	Difficulty	Time	Topic
1.	Longest Palindromic Substring	Medium	25 mins	String
2.	Word Ladder	Hard	45 mins	Graph
3.	Basic Calculator	Hard	40 mins	Stack
4.	Maximum Profit in Job Scheduling	Hard	45 mins	Binary Search
5.	Merge k Sorted Lists	Hard	30 mins	Heap
6.	Largest Rectangle in Histogram	Hard	35 mins	Stack
7.	Maximum Depth of Binary Tree	Easy	15 mins	Binary Tree

Week 8

#	Problem	Difficulty	Time	Topic
1	Contains Duplicate	Easy	15 mins	Array
2	Unique Paths	Medium	20 mins	Dynamic Programming
3	Construct Binary Tree from Preorder and Inorder Traversal	Medium	25 mins	Binary Tree
4	Container With Most Water	Medium	35 mins	Array
5	Letter Combinations of a Phone Number	Medium	30 mins	Recursion
6	Word Search	Medium	30 mins	Graph
7	Find All Anagrams in a String	Medium	30 mins	String
8	Minimum Height Trees	Medium	30 mins	Graph
9	Task Scheduler	Medium	35 mins	Heap
10	LRU Cache	Medium	30 mins	Linked List
11	Kth Smallest Element in a BST	Medium	25 mins	Binary Search Tree