Top Interview 150

Dynamic Programming String Two Pointers

#5

Longest Palindromic Substring

Medium✓ Solution📹 Video

#9

Palindrome Number

Easy✓ Solution📹 Video

Math

Backtracking Hash Table String

#17

Letter Combinations of a Phone Number

Medium✓ Solution📹 Video

Backtracking Dynamic Programming String

#22

Generate Parentheses

Medium✓ Solution📹 Video

Divide and Conquer Heap (Priority Queue)Linked List+1

#23

Merge k Sorted Lists

Hard✓ Solution📹 Video

#33

Search in Rotated Sorted Array

Medium✓ Solution📹 Video

#34

Find First and Last Position of Element in Sorted Array

Medium✓ Solution📹 Video

#35

Search Insert Position

Easy✓ Solution📹 Video

#39

Combination Sum

Medium✓ Solution📹 Video

Array Backtracking

#46

Permutations

Medium✓ Solution📹 Video

Array Backtracking

#50

Pow(x, n)

Medium✓ Solution📹 Video

Math Recursion

#52

N-Queens II

Hard✓ Solution📹 Video

Backtracking

Array Divide and Conquer Dynamic Programming

#53

Maximum Subarray

Medium✓ Solution📹 Video

Array Dynamic Programming Matrix

#63

Unique Paths II

Medium✓ Solution📹 Video

Array Dynamic Programming Matrix

#64

Minimum Path Sum

Medium✓ Solution📹 Video

#66

Plus One

Easy✓ Solution📹 Video

Array Math

#67

Add Binary

Easy✓ Solution📹 Video

Bit Manipulation Math Simulation+1

#69

Sqrt(x)

Easy✓ Solution📹 Video

Binary Search Math

Dynamic Programming Math Memoization

#70

Climbing Stairs

Easy✓ Solution📹 Video

Dynamic Programming String

#72

Edit Distance

Medium✓ Solution📹 Video

Array Binary Search Matrix

#74

Search a 2D Matrix

Medium✓ Solution📹 Video

#77

Combinations

Medium✓ Solution📹 Video

Backtracking

#79

Word Search

Medium✓ Solution📹 Video

Array Backtracking Matrix+1

Dynamic Programming String

#97

Interleaving String

Medium✓ Solution📹 Video

Binary Search Tree Binary Tree Depth-First Search+1

#98

Validate Binary Search Tree

Medium✓ Solution📹 Video

Binary Tree Breadth-First Search Tree

#103

Binary Tree Zigzag Level Order Traversal

Medium✓ Solution📹 Video

#108

Convert Sorted Array to Binary Search Tree

Easy✓ Solution📹 Video

Array Binary Search Tree Binary Tree+2

#120

Triangle

Medium✓ Solution📹 Video

#123

Best Time to Buy and Sell Stock III

Hard✓ Solution📹 Video

Breadth-First Search Hash Table String

#127

Word Ladder

Hard✓ Solution📹 Video

Array Breadth-First Search Depth-First Search+2

#130

Surrounded Regions

Medium✓ Solution📹 Video

Breadth-First Search Depth-First Search Graph+1

#133

Clone Graph

Medium✓ Solution📹 Video

#136

Single Number

Easy✓ Solution📹 Video

Array Bit Manipulation

#137

Single Number II

Medium✓ Solution📹 Video

Array Bit Manipulation

#139

Word Break

Medium✓ Solution📹 Video

Array Dynamic Programming Hash Table+3

Divide and Conquer Linked List Merge Sort+2

#148

Sort List

Medium✓ Solution📹 Video

#149

Max Points on a Line

Hard✓ Solution📹 Video

Array Geometry Hash Table+1

#153

Find Minimum in Rotated Sorted Array

Medium✓ Solution📹 Video

#162

Find Peak Element

Medium✓ Solution📹 Video

#172

Factorial Trailing Zeroes

Medium✓ Solution📹 Video

Math

#188

Best Time to Buy and Sell Stock IV

Hard✓ Solution📹 Video

Bit Manipulation Divide and Conquer

#190

Reverse Bits

Easy✓ Solution📹 Video

Bit Manipulation Divide and Conquer

#191

Number of 1 Bits

Easy✓ Solution📹 Video

#198

House Robber

Medium✓ Solution📹 Video

Array Breadth-First Search Depth-First Search+2

#200

Number of Islands

Medium✓ Solution📹 Video

#201

Bitwise AND of Numbers Range

Medium✓ Solution📹 Video

Bit Manipulation

Breadth-First Search Depth-First Search Graph+1

#207

Course Schedule

Medium✓ Solution📹 Video

#208

Implement Trie (Prefix Tree)

Medium✓ Solution📹 Video

Design Hash Table String+1

Breadth-First Search Depth-First Search Graph+1

#210

Course Schedule II

Medium✓ Solution📹 Video

#211

Design Add and Search Words Data Structure

Medium✓ Solution📹 Video

Depth-First Search Design String+1

#212

Word Search II

Hard✓ Solution📹 Video

Array Backtracking Matrix+2

Array Divide and Conquer Heap (Priority Queue)+2

#215

Kth Largest Element in an Array

Medium✓ Solution📹 Video

Array Dynamic Programming Matrix

#221

Maximal Square

Medium✓ Solution📹 Video

Binary Search Tree Binary Tree Depth-First Search+1

#230

Kth Smallest Element in a BST

Medium✓ Solution📹 Video

Data Stream Design Heap (Priority Queue)+2

#295

Find Median from Data Stream

Hard✓ Solution📹 Video

Array Binary Search Dynamic Programming

#300

Longest Increasing Subsequence

Medium✓ Solution📹 Video

Array Breadth-First Search Dynamic Programming

#322

Coin Change

Medium✓ Solution📹 Video

Array Heap (Priority Queue)

#373

Find K Pairs with Smallest Sums

Medium✓ Solution📹 Video

Array Breadth-First Search Depth-First Search+4

#399

Evaluate Division

Medium✓ Solution📹 Video

#427

Construct Quad Tree

Medium✓ Solution📹 Video

Array Divide and Conquer Matrix+1

Breadth-First Search Hash Table String

#433

Minimum Genetic Mutation

Medium✓ Solution📹 Video

#502

IPO

Hard✓ Solution📹 Video

Array Greedy Heap (Priority Queue)+1

Binary Search Tree Binary Tree Breadth-First Search+2

#530

Minimum Absolute Difference in BST

Easy✓ Solution📹 Video

Array Breadth-First Search Matrix

#909

Snakes and Ladders

Medium✓ Solution📹 Video

Array Divide and Conquer Dynamic Programming+2

#918

Maximum Sum Circular Subarray

Medium✓ Solution📹 Video

#1

Two Sum

Easy✓ Solution📹 Video

Array Hash Table

Linked List Math Recursion

#2

Add Two Numbers

Medium✓ Solution📹 Video

Hash Table Sliding Window String

#3

Longest Substring Without Repeating Characters

Medium✓ Solution📹 Video

#6

Zigzag Conversion

Medium✓ Solution📹 Video

String

Array Greedy Two Pointers

#11

Container With Most Water

Medium✓ Solution📹 Video

#12

Integer to Roman

Medium✓ Solution📹 Video

Hash Table Math String

#13

Roman to Integer

Easy✓ Solution📹 Video

Hash Table Math String

#14

Longest Common Prefix

Easy✓ Solution📹 Video

String Trie

Array Sorting Two Pointers

#15

3Sum

Medium✓ Solution📹 Video

#19

Remove Nth Node From End of List

Medium✓ Solution📹 Video

Linked List Two Pointers

#20

Valid Parentheses

Easy✓ Solution📹 Video

Stack String

#21

Merge Two Sorted Lists

Easy✓ Solution📹 Video

Linked List Recursion

#25

Reverse Nodes in k-Group

Hard✓ Solution📹 Video

Linked List Recursion

#26

Remove Duplicates from Sorted Array

Easy✓ Solution📹 Video

Array Two Pointers

#27

Remove Element

Easy✓ Solution📹 Video

Array Two Pointers

String String Matching Two Pointers

#28

Find the Index of the First Occurrence in a String

Easy✓ Solution📹 Video

Hash Table Sliding Window String

#30

Substring with Concatenation of All Words

Hard✓ Solution📹 Video

#36

Valid Sudoku

Medium✓ Solution📹 Video

Array Hash Table Matrix

Array Dynamic Programming Monotonic Stack+2

#42

Trapping Rain Water

Hard✓ Solution📹 Video

Array Dynamic Programming Greedy

#45

Jump Game II

Medium✓ Solution📹 Video

#48

Rotate Image

Medium✓ Solution📹 Video

Array Math Matrix

#49

Group Anagrams

Medium✓ Solution📹 Video

Array Hash Table Sorting+1

#54

Spiral Matrix

Medium✓ Solution📹 Video

Array Matrix Simulation

Array Dynamic Programming Greedy

#55

Jump Game

Medium✓ Solution📹 Video

#56

Merge Intervals

Medium✓ Solution📹 Video

Array Sorting

#57

Insert Interval

Medium✓ Solution📹 Video

Array

#58

Length of Last Word

Easy✓ Solution📹 Video

String

#61

Rotate List

Medium✓ Solution📹 Video

Linked List Two Pointers

#68

Text Justification

Hard✓ Solution📹 Video

Array Simulation String

#71

Simplify Path

Medium✓ Solution📹 Video

Stack String

#73

Set Matrix Zeroes

Medium✓ Solution📹 Video

Array Hash Table Matrix

Hash Table Sliding Window String

#76

Minimum Window Substring

Hard✓ Solution📹 Video

#80

Remove Duplicates from Sorted Array II

Medium✓ Solution📹 Video

Array Two Pointers

#82

Remove Duplicates from Sorted List II

Medium✓ Solution📹 Video

Linked List Two Pointers