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

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All tracksBlind 75NeetCode 150NeetCode 250Striver A to ZSDE Sheet

Showing 1-25 of 42 matching problems in NeetCode 250.

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All topics0-1 KnapsackAlgorithm XArrayBacktrackingBellman–Ford AlgorithmBidirectional SearchBinary LiftingBinary SearchBinary Search TreeBinary TreeBit ManipulationBitmaskBorůvka's AlgorithmBoyer–Moore Majority Vote AlgorithmBracket SequencesBreadth-First SearchBrute-Force SearchBubble Sort

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StatusTitleDifficulty
79. Word SearchOpen sourceMedium
94. Binary Tree Inorder TraversalOpen sourceEasy
98. Validate Binary Search TreeOpen sourceMedium
100. Same TreeOpen sourceEasy
104. Maximum Depth of Binary TreeOpen sourceEasy
110. Balanced Binary TreeOpen sourceEasy
124. Binary Tree Maximum Path SumOpen sourceHard
130. Surrounded RegionsOpen sourceMedium
133. Clone GraphOpen sourceMedium
144. Binary Tree Preorder TraversalOpen sourceEasy
145. Binary Tree Postorder TraversalOpen sourceEasy
199. Binary Tree Right Side ViewOpen sourceMedium
200. Number of IslandsOpen sourceMedium
207. Course ScheduleOpen sourceMedium
210. Course Schedule IIOpen sourceMedium
211. Design Add and Search Words Data StructureOpen sourceMedium
226. Invert Binary TreeOpen sourceEasy
230. Kth Smallest Element in a BSTOpen sourceMedium
235. Lowest Common Ancestor of a Binary Search TreeOpen sourceMedium
261. Graph Valid TreeOpen sourcePremiumMedium
269. Alien DictionaryOpen sourcePremiumHard
297. Serialize and Deserialize Binary TreeOpen sourceHard
310. Minimum Height TreesOpen sourceMedium
323. Number of Connected Components in an Undirected GraphOpen sourcePremiumMedium
329. Longest Increasing Path in a MatrixOpen sourceHard