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Top 50 leetcode Interview Questions

The most frequently asked leetcode questions across all roles and companies, ranked by real interview frequency. Updated daily.

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CodingStart here. 49 questions · ~1220 min
Two Sum Coding ProblemEasy
Practice
Recently asked

Find two array values that sum to a target using a hash map in O(n) time.

leetcodeAlgorithmsBooz Allen HamiltonVanguardAscendion
Longest Substring Without RepeatsMedium
Practice
Recently asked

Use a sliding window and hash map to find the longest substring with no repeated characters in O(n) time.

deduplicationleetcodeArraysBBeaconfiresolutionPrime VideoTTestMu AI
Coding: Stack And QueueEasy
Practice
Recently asked

Implement a constant-time minimum stack and an amortized constant-time queue using two stacks.

StackQueueleetcodeJPMorganChaseCrc Insurance ServicesUnited Airlines
3Sum Coding ProblemMedium
Practice
Recently asked

Find all unique triplets summing to zero using sorting and a two-pointer scan.

leetcodeAAcko General InsuranceCloudflarePlangrid
Meeting Room IntervalsEasy
Practice
Recently asked

Calculate the minimum rooms needed for overlapping Splunk meeting intervals using sorting and a min-heap.

intervalsleetcodeSplunkCompass
String Compression CodingMedium
Practice
Recently asked

Compress consecutive characters in place using read and write pointers with constant auxiliary space.

leetcodestring manipulationInfineon TechnologiesAffirm
Sparse Vector Dot ProductEasy
Practice
Recently asked

Compute a sparse vector dot product efficiently by processing only nonzero entries.

leetcodeMeta PlatformsAnduril
Sliding Window CodingMedium
Practice
Recently asked

Use a sliding window to find the longest contiguous Foundry event sequence with no repeated event type.

leetcodeSliding WindowPalantir technologiesPalantirDDruva
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