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CodeTutor - Coding Interview Preparation
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Showing 16 of 216 questions
Surrounded Regions
Medium
Arrays
Graphs
DFS (Depth-First Search)
BFS (Breadth-First Search)
★
Matrix Traversal
LeetCode #130
Target Sum
Medium
Arrays
Dynamic Programming
Dynamic Programming
1
2
3
4
5
6
7
8
9
10
11
★
Backtracking
LeetCode #494
Task Scheduler
Medium
Heap
Arrays
Hash Tables
Greedy
★
Heap / Priority Queue
LeetCode #621
3Sum Closest
Medium
Arrays
Two Pointers
Sorting
Two Pointers
★
LeetCode #16
3Sum
Medium
Arrays
Two Pointers
Sorting
Two Pointers
★
LeetCode #15
Top K Frequent Elements
Medium
Heap
Sorting
Arrays
Hash Tables
Counting / Bucket Sort
★
LeetCode #347
Transpose Matrix
Easy
Arrays
Matrix Traversal
★
LeetCode #867
Trapping Rain Water
Hard
Arrays
Stack
Two Pointers
Two Pointers
Monotonic Stack
★
LeetCode #42
Two Sum
Easy
Arrays
Hash Tables
Hashing
★
LeetCode #1
Unique Number of Occurrences
Easy
Arrays
Hash Tables
Hashing
★
LeetCode #1207
Unique Paths II
Medium
Arrays
Dynamic Programming
Dynamic Programming
Matrix Traversal
★
LeetCode #63
Unique Paths
Medium
Arrays
Dynamic Programming
Math
Dynamic Programming
★
LeetCode #62
Valid Sudoku
Medium
Arrays
Hash Tables
Matrix Traversal
★
LeetCode #36
Verifying an Alien Dictionary
Easy
Arrays
Hash Tables
Strings
Two Pointers
★
LeetCode #953
Word Search II
Hard
Arrays
Recursion
Strings
Trie
★
Backtracking
Matrix Traversal
LeetCode #212
Word Search
Medium
Arrays
Recursion
Backtracking
DFS (Depth-First Search)
★
LeetCode #79