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 51-75 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
72. Edit Distance Open source	Medium	StringDynamic Programming
73. Set Matrix Zeroes Open source	Medium	ArrayHash TableMatrix
74. Search a 2D Matrix Open source	Medium	ArrayBinary SearchMatrix
75. Sort Colors Open source	Medium	ArrayTwo PointersSorting+2 more
76. Minimum Window Substring Open source	Hard	Hash TableStringSliding Window
77. Combinations Open source	Medium	Backtracking
78. Subsets Open source	Medium	ArrayBacktrackingBit Manipulation
79. Word Search Open source	Medium	ArrayStringBacktracking+2 more
81. Search in Rotated Sorted Array II Open source	Medium	ArrayBinary Search
84. Largest Rectangle in Histogram Open source	Hard	ArrayStackMonotonic Stack+1 more
88. Merge Sorted Array Open source	Easy	ArrayTwo PointersSorting
90. Subsets II Open source	Medium	ArrayBacktrackingBit Manipulation
91. Decode Ways Open source	Medium	StringDynamic Programming
92. Reverse Linked List II Open source	Medium	Linked List
94. Binary Tree Inorder Traversal Open source	Easy	StackTreeDepth-First Search+1 more
97. Interleaving String Open source	Medium	StringDynamic Programming
98. Validate Binary Search Tree Open source	Medium	TreeDepth-First SearchBinary Search Tree+1 more
100. Same Tree Open source	Easy	TreeDepth-First SearchBreadth-First Search+1 more
102. Binary Tree Level Order Traversal Open source	Medium	TreeBreadth-First SearchBinary Tree
104. Maximum Depth of Binary Tree Open source	Easy	TreeDepth-First SearchBreadth-First Search+1 more
105. Construct Binary Tree from Preorder and Inorder Traversal Open source	Medium	ArrayHash TableDivide and Conquer+2 more
110. Balanced Binary Tree Open source	Easy	TreeDepth-First SearchBinary Tree
115. Distinct Subsequences Open source	Hard	StringDynamic Programming
121. Best Time to Buy and Sell Stock Open source	Easy	ArrayDynamic Programming
122. Best Time to Buy and Sell Stock II Open source	Medium	ArrayDynamic ProgrammingGreedy