Problem Library

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

Showing 1-15 of 15 matching problems in NeetCode 250.

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Array141Dynamic Programming55String53

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Title	Difficulty	Topics
67. Add Binary Open source	Easy	MathStringBit Manipulation+1 more
78. Subsets Open source	Medium	ArrayBacktrackingBit Manipulation
90. Subsets II Open source	Medium	ArrayBacktrackingBit Manipulation
136. Single Number Open source	Easy	ArrayBit Manipulation
190. Reverse Bits Open source	Easy	Divide and ConquerBit Manipulation
191. Number of 1 Bits Open source	Easy	Divide and ConquerBit Manipulation
201. Bitwise AND of Numbers Range Open source	Medium	Bit Manipulation
268. Missing Number Open source	Easy	ArrayHash TableMath+3 more
287. Find the Duplicate Number Open source	Medium	ArrayTwo PointersBinary Search+3 more
338. Counting Bits Open source	Easy	Dynamic ProgrammingBit Manipulation
371. Sum of Two Integers Open source	Medium	MathBit Manipulation
473. Matchsticks to Square Open source	Medium	ArrayDynamic ProgrammingBacktracking+2 more
698. Partition to K Equal Sum Subsets Open source	Medium	ArrayDynamic ProgrammingBacktracking+3 more
1863. Sum of All Subset XOR Totals Open source	Easy	ArrayMathBacktracking+3 more
3133. Minimum Array End Open source	Medium	Bit Manipulation