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CodeTutor - Coding Interview Preparation
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Showing 20 of 89 questions
Add Binary
Easy
Math
Strings
Two Pointers
★
LeetCode #67
Add Strings
Easy
Math
Strings
Two Pointers
★
LeetCode #415
1
2
3
4
5
Adding Spaces to a String
Medium
Arrays
Two Pointers
Strings
Two Pointers
★
LeetCode #2109
Additive Number
Medium
Strings
Recursion
Backtracking
★
LeetCode #306
Alert Using Same Key-Card Three or More Times in a One Hour Period
Medium
Strings
Arrays
Hash Tables
Sorting
Sliding Window
★
LeetCode #1604
Alphabet Board Path
Medium
Strings
Hash Tables
Matrix Traversal
★
LeetCode #1138
Ambiguous Coordinates
Medium
Strings
Recursion
Backtracking
★
LeetCode #816
Append Characters to String to Make Subsequence
Easy
Strings
Two Pointers
Two Pointers
★
Greedy
LeetCode #2486
Apply Bitwise Operations to Make Strings Equal
Medium
Math
Strings
Greedy
★
LeetCode #2546
Backspace String Compare
Easy
Strings
Stack
Two Pointers
Two Pointers
★
LeetCode #844
Base 7
Easy
Strings
Math
Greedy
★
LeetCode #504
Basic Calculator II
Medium
Strings
Stack
Math
Monotonic Stack
★
LeetCode #227
Basic Calculator IV
Hard
Hash Tables
Recursion
Math
Strings
Stack
Backtracking
★
LeetCode #770
Basic Calculator
Hard
Strings
Stack
Math
Monotonic Stack
★
LeetCode #224
Binary String With Substrings Representing 1 To N
Medium
Strings
Math
Sliding Window
★
LeetCode #1016
Binary Tree Paths
Easy
Strings
Recursion
Trees
DFS (Depth-First Search)
★
Backtracking
Binary Tree Traversal
LeetCode #257
Brace Expansion II
Hard
Strings
Recursion
Stack
Backtracking
DFS (Depth-First Search)
★
LeetCode #1096
Break a Palindrome
Medium
Strings
Greedy
★
LeetCode #1328
Buddy Strings
Easy
Strings
Hash Tables
Two Pointers
★
LeetCode #859
Accounts Merge
Medium
Strings
Hash Tables
Graphs
Union Find
★
DFS (Depth-First Search)
LeetCode #721