Problem Library

Master these coding challenges to ace your next technical interview. Handpicked problems with personalized spaced repetition.

All tracks Blind 75 NeetCode 150 NeetCode 250 Striver A to Z SDE Sheet

Showing 101-125 of 150 matching problems in NeetCode 150.

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All topics 0-1 Knapsack Algorithm X Array Backtracking Bidirectional Search Binary Lifting Binary Search Binary Search Tree Binary Tree Bit Manipulation Borůvka's Algorithm Bracket Sequences Breadth-First Search Brute-Force Search Bucket Sort Combinatorics Complete Knapsack Counting

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These are the topics showing up most often in your current queue.

Title	Difficulty	Topics
286. Walls and Gates Open sourcePremium	Medium	ArrayBreadth-First SearchMatrix
287. Find the Duplicate Number Open source	Medium	ArrayTwo PointersBinary Search+3 more
295. Find Median from Data Stream Open source	Hard	Two PointersDesignSorting+2 more
297. Serialize and Deserialize Binary Tree Open source	Hard	StringTreeDepth-First Search+3 more
300. Longest Increasing Subsequence Open source	Medium	ArrayBinary SearchDynamic Programming+1 more
309. Best Time to Buy and Sell Stock with Cooldown Open source	Medium	ArrayDynamic Programming
312. Burst Balloons Open source	Hard	ArrayDynamic Programming
322. Coin Change Open source	Medium	ArrayDynamic ProgrammingBreadth-First Search+2 more
323. Number of Connected Components in an Undirected Graph Open sourcePremium	Medium	Depth-First SearchBreadth-First SearchUnion-Find+1 more
329. Longest Increasing Path in a Matrix Open source	Hard	ArrayDynamic ProgrammingDepth-First Search+6 more
332. Reconstruct Itinerary Open source	Hard	ArrayStringDepth-First Search+6 more
338. Counting Bits Open source	Easy	Dynamic ProgrammingBit Manipulation
347. Top K Frequent Elements Open source	Medium	ArrayHash TableDivide and Conquer+5 more
355. Design Twitter Open source	Medium	Hash TableLinked ListDesign+1 more
371. Sum of Two Integers Open source	Medium	MathBit Manipulation
416. Partition Equal Subset Sum Open source	Medium	ArrayDynamic ProgrammingKnapsack Problem+1 more
417. Pacific Atlantic Water Flow Open source	Medium	ArrayDepth-First SearchBreadth-First Search+1 more
424. Longest Repeating Character Replacement Open source	Medium	Hash TableStringSliding Window
435. Non-overlapping Intervals Open source	Medium	ArrayDynamic ProgrammingGreedy+1 more
494. Target Sum Open source	Medium	ArrayDynamic ProgrammingBacktracking+2 more
518. Coin Change II Open source	Medium	ArrayDynamic ProgrammingKnapsack Problem+1 more
543. Diameter of Binary Tree Open source	Easy	TreeDepth-First SearchBinary Tree+1 more
567. Permutation in String Open source	Medium	Hash TableTwo PointersString+1 more
572. Subtree of Another Tree Open source	Easy	TreeDepth-First SearchString Matching+2 more
621. Task Scheduler Open source	Medium	ArrayHash TableGreedy+3 more