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Total0 / 154

Easy0 / 31

Medium0 / 102

Hard0 / 21

1	Contains Duplicate Arrays & Hashing	Easy
2	Majority Element Arrays & Hashing	Easy
3	Two Sum Arrays & Hashing	Easy
4	Valid Anagram Arrays & Hashing	Easy
5	Encode and Decode Strings Arrays & Hashing	Medium
6	Find the Duplicate Number Arrays & Hashing	Medium
7	Group Anagrams Arrays & Hashing	Medium
8	Longest Consecutive Sequence Arrays & Hashing	Medium
9	Product of Array Except Self Arrays & Hashing	Medium
10	Subarray Sum Equals K Arrays & Hashing	Medium
11	Top K Frequent Elements Arrays & Hashing	Medium
12	Valid Sudoku Arrays & Hashing	Medium

1	Move Zeroes Two Pointers	Easy
2	Valid Palindrome Two Pointers	Easy
3	3Sum Two Pointers	Medium
4	Container With Most Water Two Pointers	Medium
5	Two Sum II - Input Array Is Sorted Two Pointers	Medium
6	Trapping Rain Water Two Pointers	Hard

1	Best Time to Buy and Sell Stock Sliding Window	Easy
2	Longest Repeating Character Replacement Sliding Window	Medium
3	Longest Substring Without Repeating Characters Sliding Window	Medium
4	Minimum Window Substring Sliding Window	Medium
5	Permutation in String Sliding Window	Medium
6	Sliding Window Maximum Sliding Window	Hard

1	Valid Parentheses Stack	Easy
2	Car Fleet Stack	Medium
3	Daily Temperatures Stack	Medium
4	Evaluate Reverse Polish Notation Stack	Medium
5	Generate Parentheses Stack	Medium
6	Min Stack Stack	Medium
7	Largest Rectangle in Histogram Stack	Hard

1	Binary Search Binary Search	Easy
2	First Bad Version Binary Search	Easy
3	Find Minimum in Rotated Sorted Array Binary Search	Medium
4	Koko Eating Bananas Binary Search	Medium
5	Search a 2D Matrix Binary Search	Medium
6	Search in Rotated Sorted Array Binary Search	Medium
7	Time Based Key-Value Store Binary Search	Medium
8	Median of Two Sorted Arrays Binary Search	Hard

1	Linked List Cycle Linked Lists	Easy
2	Merge Two Sorted Lists Linked Lists	Easy
3	Reverse Linked List Linked Lists	Easy
4	Add Two Numbers Linked Lists	Medium
5	Copy List with Random Pointer Linked Lists	Medium
6	Remove Nth Node From End of List Linked Lists	Medium
7	Reorder List Linked Lists	Medium
8	Merge K Sorted Lists Linked Lists	Hard
9	Reverse Nodes in k-Group Linked Lists	Hard

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

1	Kth Largest Element in a Stream Heap / Priority Queue	Easy
2	Last Stone Weight Heap / Priority Queue	Easy
3	K Closest Points to Origin Heap / Priority Queue	Medium
4	Kth Largest Element in an Array Heap / Priority Queue	Medium
5	Task Scheduler Heap / Priority Queue	Medium
6	Find Median from Data Stream Heap / Priority Queue	Hard

1	Meeting Rooms Intervals	Easy
2	Insert Interval Intervals	Medium
3	Meeting Rooms II Intervals	Medium
4	Merge Intervals Intervals	Medium
5	Non-overlapping Intervals Intervals	Medium
6	Minimum Interval to Include Each Query Intervals	Hard

1	Clone Graph Graphs	Medium
2	Course Schedule Graphs	Medium
3	Course Schedule II Graphs	Medium
4	Graph Valid Tree Graphs	Medium
5	Max Area of Island Graphs	Medium
6	Number of Connected Components in an Undirected Graph Graphs	Medium
7	Number of Islands Graphs	Medium
8	Pacific Atlantic Water Flow Graphs	Medium
9	Redundant Connection Graphs	Medium
10	Rotting Oranges Graphs	Medium
11	Surrounded Regions Graphs	Medium
12	Walls and Gates Graphs	Medium
13	Word Ladder Graphs	Hard

1	Cheapest Flights Within K Stops Advanced Graphs	Medium
2	Min Cost to Connect All Points Advanced Graphs	Medium
3	Network Delay Time Advanced Graphs	Medium
4	Alien Dictionary Advanced Graphs	Hard
5	Reconstruct Itinerary Advanced Graphs	Hard
6	Swim in Rising Water Advanced Graphs	Hard

1	Climbing Stairs 1-D Dynamic Programming	Easy
2	Min Cost Climbing Stairs 1-D Dynamic Programming	Easy
3	Coin Change 1-D Dynamic Programming	Medium
4	Decode Ways 1-D Dynamic Programming	Medium
5	House Robber 1-D Dynamic Programming	Medium
6	House Robber II 1-D Dynamic Programming	Medium
7	Longest Increasing Subsequence 1-D Dynamic Programming	Medium
8	Longest Palindromic Substring 1-D Dynamic Programming	Medium
9	Maximum Product Subarray 1-D Dynamic Programming	Medium
10	Maximum Subarray 1-D Dynamic Programming	Medium
11	Palindromic Substrings 1-D Dynamic Programming	Medium
12	Partition Equal Subset Sum 1-D Dynamic Programming	Medium
13	Word Break 1-D Dynamic Programming	Medium

1	Best Time to Buy and Sell Stock with Cooldown 2-D Dynamic Programming	Medium
2	Coin Change II 2-D Dynamic Programming	Medium
3	Interleaving String 2-D Dynamic Programming	Medium
4	Longest Common Subsequence 2-D Dynamic Programming	Medium
5	Target Sum 2-D Dynamic Programming	Medium
6	Unique Paths 2-D Dynamic Programming	Medium
7	Burst Balloons 2-D Dynamic Programming	Hard
8	Distinct Subsequences 2-D Dynamic Programming	Hard
9	Edit Distance 2-D Dynamic Programming	Hard
10	Longest Increasing Path in a Matrix 2-D Dynamic Programming	Hard
11	Regular Expression Matching 2-D Dynamic Programming	Hard

1	Gas Station Greedy	Medium
2	Hand of Straights Greedy	Medium
3	Jump Game Greedy	Medium
4	Jump Game II Greedy	Medium
5	Merge Triplets to Form Target Triplet Greedy	Medium
6	Partition Labels Greedy	Medium
7	Valid Parenthesis String Greedy	Medium

1	Combination Sum Backtracking	Medium
2	Combination Sum II Backtracking	Medium
3	Letter Combinations of a Phone Number Backtracking	Medium
4	Palindrome Partitioning Backtracking	Medium
5	Permutations Backtracking	Medium
6	Subsets Backtracking	Medium
7	Subsets II Backtracking	Medium
8	Word Search Backtracking	Medium
9	N-Queens Backtracking	Hard

1	Design Add and Search Words Data Structure Tries	Medium
2	Implement Trie (Prefix Tree) Tries	Medium
3	Word Search II Tries	Hard

1	Counting Bits Bit Manipulation	Easy
2	Missing Number Bit Manipulation	Easy
3	Number of 1 Bits Bit Manipulation	Easy
4	Reverse Bits Bit Manipulation	Easy
5	Single Number Bit Manipulation	Easy
6	Sum of Two Integers Bit Manipulation	Medium

1	Happy Number Math & Geometry	Easy
2	Plus One Math & Geometry	Easy
3	Detect Squares Math & Geometry	Medium
4	Multiply Strings Math & Geometry	Medium
5	Pow(x, n) Math & Geometry	Medium
6	Reverse Integer Math & Geometry	Medium
7	Rotate Image Math & Geometry	Medium
8	Set Matrix Zeroes Math & Geometry	Medium
9	Spiral Matrix Math & Geometry	Medium

1	Design Twitter Design	Medium
2	LRU Cache Design	Medium

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