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CodeTutor - Coding Interview Preparation
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Showing 18 of 78 questions
Minimum Window Substring
Hard
Strings
Hash Tables
Sliding Window
★
LeetCode #76
Open the Lock
Medium
Strings
Hash Tables
Graphs
BFS (Breadth-First Search)
★
LeetCode #752
1
2
3
4
Partition Labels
Medium
Hash Tables
Strings
Two Pointers
Greedy
Two Pointers
★
LeetCode #763
Permutation in String
Medium
Strings
Two Pointers
Hash Tables
Sliding Window
★
LeetCode #567
Reorganize String
Medium
Hash Tables
Strings
Heap
Heap / Priority Queue
★
Greedy
LeetCode #767
Roman to Integer
Easy
Strings
Hash Tables
Math
Greedy
★
LeetCode #13
Set Matrix Zeroes
Medium
Arrays
Hash Tables
Matrix Traversal
★
LeetCode #73
Subarray Sum Equals K
Medium
Arrays
Hash Tables
Prefix Sum
★
LeetCode #560
Task Scheduler
Medium
Heap
Arrays
Hash Tables
Greedy
★
Heap / Priority Queue
LeetCode #621
Top K Frequent Elements
Medium
Heap
Sorting
Arrays
Hash Tables
Counting / Bucket Sort
★
LeetCode #347
Two Sum
Easy
Arrays
Hash Tables
Hashing
★
LeetCode #1
Unique Number of Occurrences
Easy
Arrays
Hash Tables
Hashing
★
LeetCode #1207
Valid Anagram
Easy
Strings
Hash Tables
Sorting
Hashing
★
LeetCode #242
Valid Sudoku
Medium
Arrays
Hash Tables
Matrix Traversal
★
LeetCode #36
Verifying an Alien Dictionary
Easy
Arrays
Hash Tables
Strings
Two Pointers
★
LeetCode #953
Word Break II
Hard
Strings
Hash Tables
Dynamic Programming
Backtracking
Dynamic Programming
★
LeetCode #140
Word Break
Medium
Dynamic Programming
Hash Tables
Strings
Dynamic Programming
★
LeetCode #139
Word Ladder
Hard
Strings
Hash Tables
Graphs
BFS (Breadth-First Search)
★
LeetCode #127