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Counting Interview Questions

10 Counting problems asked across FAANG and top tech companies. Approach hints, optimal solutions, and related problems.

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Companies

Amazon2Atlassian2Anduril1Bloomberg1Databricks1DE Shaw1Goldman Sachs1Google1JPMorgan1Oracle1Rippling1Salesforce1

Topics

Array 240Hash Table 113String 112Depth-First Search 73Sorting 66Dynamic Programming 65Breadth-First Search 56Math 49Design 46Binary Search 44Greedy 43Tree 41Two Pointers 39Heap 35Stack 32Graph 28Matrix 28Sliding Window 26Binary Tree 23Backtracking 22Bit Manipulation 20Prefix Sum 20Simulation 20Union Find 19Linked List 18Queue 13Trie 12Counting 10Recursion 10Divide and Conquer 9Monotonic Stack 9Ordered Set 9Topological Sort 9Data Stream 8Database 6Enumeration 6Binary Search Tree 5Doubly-Linked List 5Geometry 5+22 more

✓ 0ProblemsDifficultyAsked atPractice

169.Majority Element

ArrayHash TableDivide and Conquer

Easy▶ Mock

Easy

🔒 LeetCode▶ Mock

900.RLE Iterator

ArrayDesignCounting

Medium▶ Mock

Medium

🔒 LeetCode▶ Mock

1366.Rank Teams by Votes

ArrayHash TableString

Medium▶ Mock

Medium

🔒 LeetCode▶ Mock

767.Reorganize String

Hash TableStringGreedy

Medium▶ Mock

Medium

🔒 LeetCode▶ Mock

3035.Maximum Palindromes After Operations

ArrayHash TableString

Medium▶ Mock

Medium

🔒 LeetCode▶ Mock

692.Top K Frequent Words

ArrayHash TableString

Medium▶ Mock

Medium

🔒 LeetCode▶ Mock

1010.Pairs of Songs With Total Durations Divisible by 60

ArrayHash TableCounting

Medium▶ Mock

Medium

🔒 LeetCode▶ Mock

383.Ransom Note

Hash TableStringCounting

Easy▶ Mock

Easy

🔒 LeetCode▶ Mock

387.First Unique Character in a String

Hash TableStringQueue

Easy▶ Mock

Easy

🔒 LeetCode▶ Mock

1347.Minimum Number of Steps to Make Two Strings Anagram

Hash TableStringCounting

Medium▶ Mock

Medium

🔒 LeetCode▶ Mock