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142 problems| Problem | Difficulty | Tags | Frequency | Freshness | LeetCode | NeetCode |
|---|---|---|---|---|---|---|
3Sum | Medium | ArrayTwo PointersSorting | — | — | ||
Add Two Numbers | Medium | Linked ListMathRecursion | — | — | ||
Alien Dictionary | Hard | ArrayStringDFS+3 | — | — | ||
Balanced Binary Tree | Easy | TreeDFSBinary Tree | — | — | ||
Best Time to Buy and Sell Stock | Easy | ArrayDynamic Programming | — | — | ||
Best Time to Buy and Sell Stock with Cooldown | Medium | ArrayDynamic Programming | — | — | ||
Binary Search | Easy | ArrayBinary Search | — | — | ||
Binary Tree Level Order Traversal | Medium | TreeBFSBinary Tree | — | — | ||
Binary Tree Maximum Path Sum | Hard | Dynamic ProgrammingTreeDFS+1 | — | — | ||
Binary Tree Right Side View | Medium | TreeDFSBFS+1 | — | — | ||
Burst Balloons | Hard | ArrayDynamic Programming | — | — | ||
Car Fleet | Medium | ArrayStackSorting+1 | — | — | ||
Cheapest Flights Within K Stops | Medium | Dynamic ProgrammingDFSBFS+3 | — | — | ||
Climbing Stairs | Easy | MathDynamic ProgrammingMemoization | — | — | ||
Clone Graph | Medium | Hash TableDFSBFS+1 | — | — | ||
Coin Change | Medium | ArrayDynamic ProgrammingBFS | — | — | ||
Coin Change II | Medium | ArrayDynamic Programming | — | — | ||
Combination Sum | Medium | ArrayBacktracking | — | — | ||
Combination Sum II | Medium | ArrayBacktracking | — | — | ||
Construct Binary Tree from Preorder and Inorder Traversal | Medium | ArrayHash TableDivide and Conquer+2 | — | — | ||
Container With Most Water | Medium | ArrayTwo PointersGreedy | — | — | ||
Contains Duplicate | Easy | ArrayHash TableSorting | — | — | ||
Copy List With Random Pointer | Medium | Hash TableLinked List | — | — | ||
Count Good Nodes in Binary Tree | Medium | TreeDFSBFS+1 | — | — | ||
Counting Bits | Easy | Dynamic ProgrammingBit Manipulation | — | — | ||
Course Schedule | Medium | DFSBFSGraph+1 | — | — | ||
Course Schedule II | Medium | DFSBFSGraph+1 | — | — | ||
Daily Temperatures | Medium | ArrayStackMonotonic Stack | — | — | ||
Decode Ways | Medium | StringDynamic Programming | — | — | ||
Design Add and Search Words Data Structure | Medium | StringDFSDesign+1 | — | — | ||
Design Twitter | Medium | Hash TableLinked ListDesign+1 | — | — | ||
Detect Squares | Medium | ArrayHash TableDesign+1 | — | — | ||
Diameter of Binary Tree | Easy | TreeDFSBinary Tree | — | — | ||
Edit Distance | Medium | StringDynamic Programming | — | — | ||
Encode and Decode Strings | Medium | ArrayStringDesign | — | — | ||
Evaluate Reverse Polish Notation | Medium | ArrayMathStack | — | — | ||
Find Median from Data Stream | Hard | Two PointersDesignSorting+2 | — | — | ||
Find Minimum in Rotated Sorted Array | Medium | ArrayBinary Search | — | — | ||
Find the Duplicate Number | Medium | ArrayTwo PointersBinary Search+1 | — | — | ||
Gas Station | Medium | ArrayGreedy | — | — | ||
Generate Parentheses | Medium | StringDynamic ProgrammingBacktracking | — | — | ||
Graph Valid Tree | Medium | DFSBFSUnion Find+1 | — | — | ||
Group Anagrams | Medium | ArrayHash TableString+1 | — | — | ||
Hand of Straights | Medium | ArrayHash TableGreedy+1 | — | — | ||
Happy Number | Easy | Hash TableMathTwo Pointers | — | — | ||
House Robber | Medium | ArrayDynamic Programming | — | — | ||
House Robber II | Medium | ArrayDynamic Programming | — | — | ||
Implement Trie (Prefix Tree) | Medium | Hash TableStringDesign+1 | — | — | ||
Insert Interval | Medium | Array | — | — | ||
Interleaving String | Medium | StringDynamic ProgrammingMemoization | — | — | ||
Invert Binary Tree | Easy | TreeDFSBFS+1 | — | — | ||
Jump Game | Medium | ArrayDynamic ProgrammingGreedy | — | — | ||
Jump Game II | Medium | ArrayDynamic ProgrammingGreedy | — | — | ||
K Closest Points to Origin | Medium | ArrayMathDivide and Conquer+3 | — | — | ||
Koko Eating Bananas | Medium | ArrayBinary Search | — | — | ||
Kth Largest Element in a Stream | Easy | TreeDesignBinary Search Tree+2 | — | — | ||
Kth Smallest Element in a BST | Medium | TreeDFSBinary Search Tree+1 | — | — | ||
Largest Rectangle in Histogram | Hard | ArrayStackMonotonic Stack | — | — | ||
Last Stone Weight | Easy | ArrayHeap | — | — | ||
Letter Combinations of a Phone Number | Medium | Hash TableStringBacktracking | — | — | ||
Linked List Cycle | Easy | Hash TableLinked ListTwo Pointers | — | — | ||
Longest Common Subsequence | Medium | StringDynamic Programming | — | — | ||
Longest Consecutive Sequence | Medium | ArrayHash TableUnion Find | — | — | ||
Longest Increasing Subsequence | Medium | ArrayBinary SearchDynamic Programming | — | — | ||
Longest Palindromic Substring | Medium | Two PointersStringDynamic Programming | — | — | ||
Longest Repeating Character Replacement | Medium | Hash TableStringSliding Window | — | — | ||
Longest Substring Without Repeating Characters | Medium | Hash TableStringSliding Window | — | — | ||
Lowest Common Ancestor of a BST | Medium | TreeDFSBinary Search Tree+1 | — | — | ||
LRU Cache | Medium | Hash TableLinked ListDesign+1 | — | — | ||
Max Area of Island | Medium | ArrayDFSBFS+2 | — | — | ||
Maximum Depth of Binary Tree | Easy | TreeDFSBFS+1 | — | — | ||
Maximum Product Subarray | Medium | ArrayDynamic Programming | — | — | ||
Maximum Subarray | Medium | ArrayDivide and ConquerDynamic Programming | — | — | ||
Median of Two Sorted Arrays | Hard | ArrayBinary SearchDivide and Conquer | — | — | ||
Meeting Rooms | Easy | ArraySorting | — | — | ||
Meeting Rooms II | Medium | ArrayTwo PointersGreedy+2 | — | — | ||
Merge Intervals | Medium | ArraySorting | — | — | ||
Merge K Sorted Lists | Hard | Linked ListDivide and ConquerHeap+1 | — | — | ||
Merge Triplets to Form Target Triplet | Medium | ArrayGreedy | — | — | ||
Merge Two Sorted Lists | Easy | Linked ListRecursion | — | — | ||
Min Cost Climbing Stairs | Easy | ArrayDynamic Programming | — | — | ||
Min Cost to Connect All Points | Medium | ArrayUnion FindGraph+2 | — | — | ||
Min Stack | Medium | StackDesign | — | — | ||
Minimum Window Substring | Hard | Hash TableStringSliding Window | — | — | ||
Missing Number | Easy | ArrayHash TableMath+3 | — | — | ||
Multiply Strings | Medium | MathStringSimulation | — | — | ||
N-Queens | Hard | ArrayBacktracking | — | — | ||
Network Delay Time | Medium | DFSBFSGraph+2 | — | — | ||
Non-overlapping Intervals | Medium | ArrayDynamic ProgrammingGreedy+1 | — | — | ||
Number of 1 Bits | Easy | Divide and ConquerBit Manipulation | — | — | ||
Number of Connected Components in an Undirected Graph | Medium | DFSBFSUnion Find+1 | — | — | ||
Number of Islands | Medium | ArrayDFSBFS+2 | — | — | ||
Pacific Atlantic Water Flow | Medium | ArrayDFSBFS+1 | — | — | ||
Palindrome Partitioning | Medium | StringDynamic ProgrammingBacktracking | — | — | ||
Palindromic Substrings | Medium | Two PointersStringDynamic Programming | — | — | ||
Partition Equal Subset Sum | Medium | ArrayDynamic Programming | — | — | ||
Partition Labels | Medium | Hash TableTwo PointersString+1 | — | — | ||
Permutation in String | Medium | Hash TableTwo PointersString+1 | — | — | ||
Permutations | Medium | ArrayBacktracking | — | — | ||
Plus One | Easy | ArrayMath | — | — | ||
Pow(x, n) | Medium | MathRecursion | — | — | ||
Product of Array Except Self | Medium | ArrayPrefix Sum | — | — | ||
Reconstruct Itinerary | Hard | DFSGraphEulerian Circuit | — | — | ||
Regular Expression Matching | Hard | StringDynamic ProgrammingRecursion | — | — | ||
Remove Nth Node From End of List | Medium | Linked ListTwo Pointers | — | — | ||
Reorder List | Medium | Linked ListTwo PointersStack+1 | — | — | ||
Reverse Bits | Easy | Divide and ConquerBit Manipulation | — | — | ||
Reverse Integer | Medium | Math | — | — | ||
Reverse Linked List | Easy | Linked ListRecursion | — | — | ||
Reverse Nodes in k-Group | Hard | Linked ListRecursion | — | — | ||
Rotate Image | Medium | ArrayMathMatrix | — | — | ||
Rotting Oranges | Medium | ArrayBFSMatrix | — | — | ||
Same Tree | Easy | TreeDFSBFS+1 | — | — | ||
Search a 2D Matrix | Medium | ArrayBinary SearchMatrix | — | — | ||
Search in Rotated Sorted Array | Medium | ArrayBinary Search | — | — | ||
Serialize and Deserialize Binary Tree | Hard | StringTreeDFS+3 | — | — | ||
Set Matrix Zeroes | Medium | ArrayHash TableMatrix | — | — | ||
Single Number | Easy | ArrayBit Manipulation | — | — | ||
Sliding Window Maximum | Hard | ArrayQueueSliding Window+1 | — | — | ||
Spiral Matrix | Medium | ArrayMatrixSimulation | — | — | ||
Subsets | Medium | ArrayBacktrackingBit Manipulation | — | — | ||
Subsets II | Medium | ArrayBacktrackingBit Manipulation | — | — | ||
Subtree of Another Tree | Easy | TreeDFSString Matching+2 | — | — | ||
Sum of Two Integers | Medium | MathBit Manipulation | — | — | ||
Surrounded Regions | Medium | ArrayDFSBFS+2 | — | — | ||
Swim in Rising Water | Hard | ArrayBinary SearchDFS+4 | — | — | ||
Target Sum | Medium | ArrayDynamic ProgrammingBacktracking | — | — | ||
Task Scheduler | Medium | ArrayHash TableGreedy+3 | — | — | ||
Time Based Key-Value Store | Medium | Hash TableStringBinary Search+1 | — | — | ||
Top K Frequent Elements | Medium | ArrayHash TableHeap+1 | — | — | ||
Trapping Rain Water | Hard | ArrayTwo PointersStack+1 | — | — | ||
Two Sum | Easy | ArrayHash Table | — | — | ||
Unique Paths | Medium | MathDynamic ProgrammingCombinatorics | — | — | ||
Valid Anagram | Easy | Hash TableStringSorting | — | — | ||
Valid Palindrome | Easy | Two PointersString | — | — | ||
Valid Parentheses | Easy | StringStack | — | — | ||
Validate Binary Search Tree | Medium | TreeDFSBinary Search Tree+1 | — | — | ||
Walls and Gates | Medium | ArrayBFSMatrix | — | — | ||
Word Break | Medium | ArrayHash TableString+3 | — | — | ||
Word Ladder | Hard | Hash TableStringBFS | — | — | ||
Word Search | Medium | ArrayStringBacktracking+1 | — | — | ||
Word Search II | Hard | ArrayStringBacktracking+2 | — | — |
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