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CodeTutor - Coding Interview Preparation
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Showing 20 of 216 questions
132 Pattern
Medium
Arrays
Stack
Monotonic Stack
★
LeetCode #456
24 Game
Hard
Math
Arrays
Recursion
Backtracking
★
LeetCode #679
1
2
3
4
5
6
7
8
9
10
11
3Sum With Multiplicity
Medium
Hash Tables
Arrays
Two Pointers
Counting / Bucket Sort
★
LeetCode #923
4Sum II
Medium
Arrays
Hash Tables
Hashing
★
LeetCode #454
Add Minimum Number of Rungs
Medium
Arrays
Greedy
★
LeetCode #1936
Add to Array-Form of Integer
Easy
Arrays
Math
Two Pointers
★
LeetCode #989
Adding Spaces to a String
Medium
Arrays
Two Pointers
Strings
Two Pointers
★
LeetCode #2109
Adding Two Negabinary Numbers
Medium
Arrays
Math
Two Pointers
★
LeetCode #1073
Advantage Shuffle
Medium
Sorting
Arrays
Greedy
Two Pointers
★
LeetCode #870
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 Divisions With the Highest Score of a Binary Array
Medium
Arrays
Prefix Sum
★
LeetCode #2155
Allocate Mailboxes
Hard
Sorting
Arrays
Dynamic Programming
Math
Dynamic Programming
★
LeetCode #1478
Append K Integers With Minimal Sum
Medium
Sorting
Arrays
Math
Greedy
★
LeetCode #2195
Apply Operations to an Array
Easy
Arrays
Two Pointers
Two Pointers
★
LeetCode #2460
Arithmetic Slices II - Subsequence
Hard
Arrays
Hash Tables
Dynamic Programming
Dynamic Programming
★
LeetCode #446
Arithmetic Slices
Medium
Arrays
Dynamic Programming
Dynamic Programming
★
LeetCode #413
Arithmetic Subarrays
Medium
Arrays
Hash Tables
Sorting
Two Pointers
★
LeetCode #1630
Array Nesting
Medium
Arrays
DFS (Depth-First Search)
★
LeetCode #565
Array of Doubled Pairs
Medium
Sorting
Arrays
Hash Tables
Greedy
★
LeetCode #954
01 Matrix
Medium
Arrays
Graphs
BFS (Breadth-First Search)
★
Matrix Traversal
Dynamic Programming
LeetCode #542