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 250 matching problems in NeetCode 250.

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All topics 0-1 Knapsack Algorithm X Array Backtracking Bellman–Ford Algorithm Bidirectional Search Binary Lifting Binary Search Binary Search Tree Binary Tree Bit Manipulation Bitmask Borůvka's Algorithm Boyer–Moore Majority Vote Algorithm Bracket Sequences Breadth-First Search Brute-Force Search Bubble Sort

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Array141Dynamic Programming55String53

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

Title	Difficulty	Topics
189. Rotate Array Open source	Medium	ArrayMathTwo Pointers
190. Reverse Bits Open source	Easy	Divide and ConquerBit Manipulation
191. Number of 1 Bits Open source	Easy	Divide and ConquerBit Manipulation
198. House Robber Open source	Medium	ArrayDynamic Programming
199. Binary Tree Right Side View Open source	Medium	TreeDepth-First SearchBreadth-First Search+1 more
200. Number of Islands Open source	Medium	ArrayDepth-First SearchBreadth-First Search+2 more
201. Bitwise AND of Numbers Range Open source	Medium	Bit Manipulation
202. Happy Number Open source	Easy	Hash TableMathTwo Pointers+1 more
206. Reverse Linked List Open source	Easy	Linked ListRecursion
207. Course Schedule Open source	Medium	Depth-First SearchBreadth-First SearchGraph Theory+2 more
208. Implement Trie (Prefix Tree)Open source	Medium	Hash TableStringDesign+1 more
209. Minimum Size Subarray Sum Open source	Medium	ArrayBinary SearchSliding Window+1 more
210. Course Schedule II Open source	Medium	Depth-First SearchBreadth-First SearchGraph Theory+1 more
211. Design Add and Search Words Data Structure Open source	Medium	StringDepth-First SearchDesign+1 more
212. Word Search II Open source	Hard	ArrayStringBacktracking+2 more
213. House Robber II Open source	Medium	ArrayDynamic Programming
215. Kth Largest Element in an Array Open source	Medium	ArrayDivide and ConquerSorting+2 more
217. Contains Duplicate Open source	Easy	ArrayHash TableSorting
219. Contains Duplicate II Open source	Easy	ArrayHash TableSliding Window
225. Implement Stack using Queues Open source	Easy	StackDesignQueue
226. Invert Binary Tree Open source	Easy	TreeDepth-First SearchBreadth-First Search+1 more
229. Majority Element II Open source	Medium	ArrayHash TableSorting+2 more
230. Kth Smallest Element in a BST Open source	Medium	TreeDepth-First SearchBinary Search Tree+1 more
232. Implement Queue using Stacks Open source	Easy	StackDesignQueue
235. Lowest Common Ancestor of a Binary Search Tree Open source	Medium	TreeDepth-First SearchBinary Search Tree+3 more