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CodeTutor - Coding Interview Preparation
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Arrays (216)
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Heap (18)
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Recursion (51)
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Strings (89)
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BFS (Breadth-First Search) (35)
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Binary Search (28)
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Bit Manipulation (4)
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Cyclic Sort (0)
DFS (Depth-First Search) (53)
Divide and Conquer (0)
Dynamic Programming (69)
Fast & Slow Pointers (5)
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Trie (3)
Two Pointers (62)
Union Find (8)
Showing 20 of 78 questions
Design HashMap
Easy
Arrays
Linked Lists
Hash Tables
Hashing
★
LeetCode #706
Design HashSet
Easy
Arrays
Hash Tables
Hashing
★
LeetCode #705
1
2
3
4
Design Twitter
Medium
Heap
Hash Tables
Heap / Priority Queue
★
LeetCode #355
Detect Squares
Medium
Arrays
Hash Tables
Hashing
★
LeetCode #2013
Evaluate Division
Medium
Hash Tables
Graphs
BFS (Breadth-First Search)
DFS (Depth-First Search)
Union Find
★
LeetCode #399
Find the Town Judge
Easy
Arrays
Hash Tables
Graphs
Greedy
★
LeetCode #997
First Missing Positive
Hard
Arrays
Hash Tables
Matrix Traversal
★
LeetCode #41
Group Anagrams
Medium
Sorting
Hash Tables
Strings
Hashing
★
LeetCode #49
Hand of Straights
Medium
Sorting
Arrays
Hash Tables
Greedy
★
Heap / Priority Queue
LeetCode #846
Happy Number
Easy
Math
Hash Tables
Fast & Slow Pointers
★
LeetCode #202
Implement Trie (Prefix Tree)
Medium
Strings
Hash Tables
Trie
★
LeetCode #208
Letter Combinations of a Phone Number
Medium
Strings
Recursion
Hash Tables
Backtracking
★
LeetCode #17
LFU Cache
Hard
Linked Lists
Hash Tables
Hashing
★
LeetCode #460
Linked List Cycle
Easy
Two Pointers
Hash Tables
Linked Lists
Fast & Slow Pointers
★
LeetCode #141
Longest Consecutive Sequence
Medium
Arrays
Hash Tables
Union Find
★
LeetCode #128
Longest Substring Without Repeating Characters
Medium
Strings
Hash Tables
Sliding Window
★
LeetCode #3
LRU Cache
Medium
Linked Lists
Hash Tables
LinkedList In-Place Reversal
★
LeetCode #146
Majority Element II
Medium
Arrays
Hash Tables
Greedy
★
LeetCode #229
Majority Element
Easy
Arrays
Hash Tables
Greedy
★
LeetCode #169
Maximum Frequency Stack
Hard
Stack
Hash Tables
Monotonic Stack
★
Hashing
LeetCode #895