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CodeTutor - Coding Interview Preparation
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Showing 20 of 78 questions
4Sum II
Medium
Arrays
Hash Tables
Hashing
★
LeetCode #454
Accounts Merge
Medium
Strings
Hash Tables
Graphs
Union Find
★
DFS (Depth-First Search)
1
2
3
4
LeetCode #721
Alert Using Same Key-Card Three or More Times in a One Hour Period
Medium
Strings
Arrays
Hash Tables
Sorting
Sliding Window
★
LeetCode #1604
All Nodes Distance K in Binary Tree
Medium
Trees
Hash Tables
Graphs
BFS (Breadth-First Search)
★
DFS (Depth-First Search)
LeetCode #863
Alphabet Board Path
Medium
Strings
Hash Tables
Matrix Traversal
★
LeetCode #1138
Amount of Time for Binary Tree to Be Infected
Medium
Trees
Hash Tables
Graphs
BFS (Breadth-First Search)
★
Binary Tree Traversal
LeetCode #2385
Arithmetic Slices II - Subsequence
Hard
Arrays
Hash Tables
Dynamic Programming
Dynamic Programming
★
LeetCode #446
Arithmetic Subarrays
Medium
Arrays
Hash Tables
Sorting
Two Pointers
★
LeetCode #1630
Array of Doubled Pairs
Medium
Sorting
Arrays
Hash Tables
Greedy
★
LeetCode #954
Avoid Flood in The City
Medium
Arrays
Hash Tables
Greedy
Binary Search
★
LeetCode #1488
Basic Calculator IV
Hard
Hash Tables
Recursion
Math
Strings
Stack
Backtracking
★
LeetCode #770
Best Poker Hand
Easy
Arrays
Hash Tables
Greedy
★
LeetCode #2347
Binary Subarrays With Sum
Medium
Arrays
Hash Tables
Sliding Window
★
Prefix Sum
LeetCode #930
Binary Trees With Factors
Medium
Sorting
Arrays
Hash Tables
Dynamic Programming
Dynamic Programming
★
LeetCode #823
Brick Wall
Medium
Arrays
Hash Tables
Prefix Sum
★
LeetCode #554
Buddy Strings
Easy
Strings
Hash Tables
Two Pointers
★
LeetCode #859
Bulls and Cows
Medium
Strings
Hash Tables
Two Pointers
★
LeetCode #299
Bus Routes
Hard
Arrays
Hash Tables
Graphs
BFS (Breadth-First Search)
★
LeetCode #815
Cache With Time Limit
Medium
Hash Tables
Hashing
★
LeetCode #2622
3Sum With Multiplicity
Medium
Hash Tables
Arrays
Two Pointers
Counting / Bucket Sort
★
LeetCode #923