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CodeTutor - Coding Interview Preparation
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Showing 20 of 401 questions
Minimum Size Subarray Sum
Medium
Arrays
Binary Search
Sliding Window
Binary Search
★
Prefix Sum
LeetCode #209
Merge Strings Alternately
Easy
Strings
Two Pointers
Two Pointers
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
★
LeetCode #1768
Merge Triplets to Form Target Triplet
Medium
Arrays
Greedy
★
LeetCode #1899
Merge Two Sorted Lists
Easy
Recursion
Linked Lists
Two Pointers
★
LeetCode #21
Min Cost Climbing Stairs
Easy
Arrays
Dynamic Programming
Dynamic Programming
★
LeetCode #746
Min Cost to Connect All Points
Medium
Heap
Graphs
Heap / Priority Queue
★
Union Find
LeetCode #1584
Min Stack
Medium
Stack
Monotonic Stack
★
LeetCode #155
Minimum Height Trees
Medium
Trees
Graphs
BFS (Breadth-First Search)
★
Binary Tree Traversal
LeetCode #310
Minimum Interval to Include Each Query
Hard
Arrays
Heap
Sorting
Heap / Priority Queue
★
LeetCode #1851
Minimum Path Sum
Medium
Arrays
Dynamic Programming
Dynamic Programming
Matrix Traversal
★
LeetCode #64
Minimum Window Substring
Hard
Strings
Hash Tables
Sliding Window
★
LeetCode #76
Missing Number
Easy
Arrays
Math
Prefix Sum
★
LeetCode #268
Multiply Strings
Medium
Strings
Math
Two Pointers
★
LeetCode #43
Network Delay Time
Medium
Heap
Graphs
Heap / Priority Queue
★
BFS (Breadth-First Search)
LeetCode #743
Number of 1 Bits
Easy
Math
Bit Manipulation
★
LeetCode #191
Number of Islands
Medium
Arrays
Graphs
DFS (Depth-First Search)
BFS (Breadth-First Search)
★
Matrix Traversal
LeetCode #200
1-bit and 2-bit Characters
Easy
Arrays
Greedy
★
LeetCode #717
Online Stock Span
Medium
Stack
Monotonic Stack
★
LeetCode #901
Open the Lock
Medium
Strings
Hash Tables
Graphs
BFS (Breadth-First Search)
★
LeetCode #752
Pacific Atlantic Water Flow
Medium
Arrays
Graphs
DFS (Depth-First Search)
★
Matrix Traversal
LeetCode #417