Coding Interview Questions

Click ⭐ if you like the project. Pull Request are highly appreciated. Follow me @OmBharatiya for technical updates.

---

Interview Questions

Table of Contents

SNo.	Contents
1.	FAANG Must Do Problems
2.	Amazon
3.	Microsoft
4.	Facebook
5.	Google Top 50
6.	Google

1. FAANG Must Do Problems

No.	Questions
1	Two Sum
2	Longest Substring Without Repeating Characters
3	Longest Palindromic Substring
4	Container With Most Water
5	3Sum
6	Remove Nth Node From End of List
7	Valid Parentheses
8	Merge Two Sorted Lists
9	Merge k Sorted Lists
10	Search in Rotated Sorted Array
11	Combination Sum
12	Rotate Image
13	Group Anagrams
14	Maximum Subarray
15	Spiral Matrix
16	Jump Game
17	Merge Intervals
18	Insert Interval
19	Unique Paths
20	Climbing Stairs
21	Set Matrix Zeroes
22	Minimum Window Substring
23	Word Search
24	Decode Ways
25	Validate Binary Search Tree
26	Same Tree
27	Binary Tree Level Order Traversal
28	Maximum Depth of Binary Tree
29	Construct Binary Tree from Preorder and Inorder Traversal
30	Best Time to Buy and Sell Stock
31	Binary Tree Maximum Path Sum
32	Valid Palindrome
33	Longest Consecutive Sequence
34	Clone Graph
35	Word Break
36	Linked List Cycle
37	Reorder List
38	Maximum Product Subarray
39	Find Minimum in Rotated Sorted Array
40	Reverse Bits
41	Number of 1 Bits
42	House Robber
43	Number of Islands
44	Reverse Linked List
45	Course Schedule
46	Implement Trie (Prefix Tree)
47	Design Add and Search Words Data Structure
48	Word Search II
49	House Robber II
50	Contains Duplicate
51	Invert Binary Tree
52	Kth Smallest Element in a BST
53	Lowest Common Ancestor of a Binary Search Tree
54	Lowest Common Ancestor of a Binary Tree
55	Product of Array Except Self
56	Valid Anagram
57	Meeting Rooms
58	Meeting Rooms II
59	Graph Valid Tree
60	Missing Number
61	Alien Dictionary
62	Encode and Decode Strings
63	Find Median from Data Stream
64	Longest Increasing Subsequence
65	Coin Change
66	Number of Connected Components in an Undirected Graph
67	Counting Bits
68	Top K Frequent Elements
69	Sum of Two Integers
70	Pacific Atlantic Water Flow
71	Longest Repeating Character Replacement
72	Non-overlapping Intervals
73	Serialize and Deserialize BST
74	Subtree of Another Tree
75	Palindromic Substrings
76	Longest Common Subsequence

2. Amazon

No.	Questions
1	Two Sum
2	Add Two Numbers
3	Longest Substring Without Repeating Characters
4	Median of Two Sorted Arrays
5	Longest Palindromic Substring
6	ZigZag Conversion
7	String to Integer (atoi)
8	3Sum
9	Letter Combinations of a Phone Number
10	Valid Parentheses
11	Merge Two Sorted Lists
12	Generate Parentheses
13	Merge k Sorted Lists
14	Trapping Rain Water
15	Permutations
16	Rotate Image
17	Group Anagrams
18	Merge Intervals
19	Spiral Matrix II
20	Unique Paths II
21	Minimum Path Sum
22	Edit Distance
23	Set Matrix Zeroes
24	Sort Colors
25	Minimum Window Substring
26	Subsets
27	Gray Code
28	Validate Binary Search Tree
29	Same Tree
30	Binary Tree Level Order Traversal
31	Path Sum II
32	Pascal's Triangle II
33	Best Time to Buy and Sell Stock
34	Word Ladder II
35	Word Ladder
36	Sum Root to Leaf Numbers
37	Copy List with Random Pointer
38	Word Break
39	Linked List Cycle
40	LRU Cache
41	Sort List
42	Min Stack
43	Intersection of Two Linked Lists
44	Two Sum II - Input array is sorted
45	Binary Search Tree Iterator
46	Rotate Array
47	Binary Tree Right Side View
48	Number of Islands
49	Happy Number
50	Count Primes
51	Reverse Linked List
52	Word Search II
53	Kth Largest Element in an Array
54	Basic Calculator
55	Palindrome Linked List
56	Lowest Common Ancestor of a Binary Search Tree
57	Lowest Common Ancestor of a Binary Tree
58	Product of Array Except Self
59	Sliding Window Maximum
60	Search a 2D Matrix II
61	Valid Anagram
62	Find Median from Data Stream
63	Serialize and Deserialize Binary Tree
64	Top K Frequent Elements
65	Design Twitter
66	Insert Delete GetRandom O(1)
67	Shuffle an Array
68	First Unique Character in a String
69	Rotate Function
70	Third Maximum Number
71	Battleships in a Board
72	Find All Anagrams in a String
73	String Compression
74	Serialize and Deserialize BST
75	Sort Characters By Frequency
76	Repeated Substring Pattern
77	LFU Cache
78	Concatenated Words
79	Most Frequent Subtree Sum
80	Longest Palindromic Subsequence
81	Super Washing Machines
82	Minesweeper
83	K-diff Pairs in an Array
84	Encode and Decode TinyURL
85	Complex Number Multiplication
86	Convert BST to Greater Tree
87	01 Matrix
88	Optimal Division
89	Subarray Sum Equals K
90	Subtree of Another Tree
91	Shortest Unsorted Continuous Subarray
92	Construct String from Binary Tree
93	Merge Two Binary Trees
94	Solve the Equation
95	Set Mismatch
96	Maximum Length of Pair Chain
97	Image Smoother
98	Maximum Width of Binary Tree
99	Cut Off Trees for Golf Event
100	Baseball Game
101	Top K Frequent Words
102	Accounts Merge
103	Find Pivot Index
104	Split Linked List in Parts
105	Monotone Increasing Digits
106	Min Cost Climbing Stairs
107	Prime Number of Set Bits in Binary Representation
108	Partition Labels
109	Reorganize String
110	Global and Local Inversions
111	Most Common Word
112	Unique Email Addresses
113	Knight Dialer
114	Reorder Data in Log Files
115	Prison Cells After N Days
116	K Closest Points to Origin
117	Subarrays with K Different Integers
118	Rotting Oranges
119	Binary Search Tree to Greater Sum Tree
120	Distant Barcodes
121	Sum of Nodes with Even-Valued Grandparent
122	Number of Dice Rolls With Target Sum
123	Critical Connections in a Network
124	Search Suggestions System
125	Number of Steps to Reduce a Number to Zero
126	Stone Game III

3. Microsoft

No.	Questions
1	Two Sum
2	Add Two Numbers
3	Median of Two Sorted Arrays
4	Longest Palindromic Substring
5	String to Integer (atoi)
6	Roman to Integer
7	3Sum
8	Valid Parentheses
9	Merge Two Sorted Lists
10	Merge k Sorted Lists
11	Swap Nodes in Pairs
12	Reverse Nodes in k-Group
13	Remove Duplicates from Sorted Array
14	Implement strStr()
15	Search in Rotated Sorted Array
16	Maximum Subarray
17	Spiral Matrix
18	Jump Game
19	Merge Intervals
20	Binary Tree Maximum Path Sum
21	Valid Palindrome
22	Copy List with Random Pointer
23	Linked List Cycle
24	LRU Cache
25	Reverse Words in a String
26	Find Minimum in Rotated Sorted Array
27	Find Peak Element
28	Excel Sheet Column Title
29	Excel Sheet Column Number
30	Binary Search Tree Iterator
31	Rotate Array
32	Number of 1 Bits
33	Number of Islands
34	Reverse Linked List
35	Implement Trie (Prefix Tree)
36	Word Search II
37	Kth Largest Element in an Array
38	The Skyline Problem
39	Delete Node in a Linked List
40	Product of Array Except Self
41	Add Digits
42	Missing Number
43	Serialize and Deserialize Binary Tree
44	First Unique Character in a String
45	Arithmetic Slices
46	String Compression
47	Max Chunks To Make Sorted
48	Valid Tic-Tac-Toe State
49	Maximum Length of a Concatenated String with Unique Characters
50	Find N Unique Integers Sum up to Zero
51	Jump Game III
52	Cinema Seat Allocation
53	Bulb Switcher III

3. Facebook

No.	Questions
1	Regular Expression Matching
2	Roman to Integer
3	3Sum
4	Letter Combinations of a Phone Number
5	Valid Parentheses
6	Merge k Sorted Lists
7	Reverse Nodes in k-Group
8	Remove Duplicates from Sorted Array
9	Implement strStr()
10	Search in Rotated Sorted Array
11	Count and Say
12	Wildcard Matching
13	Pow(x, n)
14	Merge Intervals
15	Insert Interval
16	Valid Palindrome
17	Longest Consecutive Sequence
18	Clone Graph
19	Word Break
20	LRU Cache
21	Binary Search Tree Iterator
22	Number of Islands
23	Implement Trie (Prefix Tree)
24	Kth Largest Element in an Array
25	The Skyline Problem
26	Maximal Square
27	Binary Tree Paths
28	H-Index
29	Expression Add Operators
30	Serialize and Deserialize Binary Tree
31	Flatten Nested List Iterator
32	Combination Sum IV
33	Insert Delete GetRandom O(1)
34	Target Sum
35	Encode and Decode TinyURL
36	Diameter of Binary Tree
37	Valid Palindrome II
38	Maximum Sum of 3 Non-Overlapping Subarrays
39	Sudoku Solver
40	Maximum Subarray
41	Valid Number
42	Plus One
43	Add Binary
44	Is Graph Bipartite?
45	Custom Sort String
46	Smallest Subtree with all the Deepest Nodes
47	Shortest Bridge
48	Range Sum of BST
49	Verifying an Alien Dictionary
50	K Closest Points to Origin
51	Interval List Intersections
52	Max Consecutive Ones III
53	Minimum Remove to Make Valid Parentheses
54	Merge Sorted Array
55	Binary Tree Level Order Traversal
56	Best Time to Buy and Sell Stock
57	Best Time to Buy and Sell Stock III
58	Best Time to Buy and Sell Stock IV
59	Binary Tree Maximum Path Sum
60	Fraction to Recurring Decimal
61	Simplify Path
62	Minimum Window Substring
63	Course Schedule
64	Design Add and Search Words Data Structure
65	Kth Smallest Element in a BST
66	Lowest Common Ancestor of a Binary Tree
67	Product of Array Except Self
68	Exclusive Time of Functions
69	First Bad Version
70	Move Zeroes
71	Task Scheduler
72	Remove Invalid Parentheses
73	Longest Increasing Path in a Matrix
74	Search in Rotated Sorted Array II
75	Convert a Number to Hexadecimal
76	Add Strings
77	Partition Equal Subset Sum
78	Find All Anagrams in a String
79	Continuous Subarray Sum
80	Subarray Sum Equals K

4. Google Top 50

No.	Questions
1	Two Sum
2	Insert Interval
3	Text Justification
4	Minimum Window Substring
5	Maximal Rectangle
6	The Skyline Problem
7	Maximal Square
8	Find Median from Data Stream
9	Bulls and Cows
10	Count of Smaller Numbers After Self
11	Longest Increasing Path in a Matrix
12	Max Sum of Rectangle No Larger Than K
13	Decode String
14	Evaluate Division
15	Split Array Largest Sum
16	Subarray Sum Equals K
17	Split Array into Consecutive Subsequences
18	24 Game
19	Network Delay Time
20	Open the Lock
21	Expressive Words
22	Find And Replace in String
23	Guess the Word
24	Hand of Straights
25	Shortest Subarray with Sum at Least K
26	Random Pick with Weight
27	X of a Kind in a Deck of Cards
28	Minimum Area Rectangle
29	Validate Stack Sequences
30	Flip Equivalent Binary Trees
31	Minimum Domino Rotations For Equal Row
32	Longest String Chain
33	Delete Nodes And Return Forest
34	Snapshot Array
35	Divide Array in Sets of K Consecutive Numbers
36	Minimum Distance to Type a Word Using Two Fingers
37	Time Needed to Inform All Employees

5. Google

No.	Questions
1	Two Sum
2	Median of Two Sorted Arrays
3	Regular Expression Matching
4	Letter Combinations of a Phone Number
5	Valid Parentheses
6	Generate Parentheses
7	Merge k Sorted Lists
8	Remove Duplicates from Sorted Array
9	Next Permutation
10	Trapping Rain Water
11	Wildcard Matching
12	Pow(x, n)
13	Spiral Matrix
14	Merge Intervals
15	Insert Interval
16	Plus One
17	Maximal Rectangle
18	Same Tree
19	Pascal's Triangle
20	Word Ladder
21	Longest Consecutive Sequence
22	Clone Graph
23	Word Break
24	Word Break II
25	LRU Cache
26	Min Stack
27	Find Peak Element
28	Fraction to Recurring Decimal
29	Binary Search Tree Iterator
30	House Robber
31	Number of Islands
32	Isomorphic Strings
33	Implement Trie (Prefix Tree)
34	Word Search II
35	Shortest Palindrome
36	The Skyline Problem
37	Count Complete Tree Nodes
38	Basic Calculator
39	Summary Ranges
40	Kth Smallest Element in a BST
41	Power of Two
42	Product of Array Except Self
43	Sliding Window Maximum
44	Search a 2D Matrix II
45	Binary Tree Paths
46	H-Index
47	Perfect Squares
48	Expression Add Operators
49	Move Zeroes
50	Peeking Iterator
51	Game of Life
52	Find Median from Data Stream
53	Serialize and Deserialize Binary Tree
54	Bulls and Cows
55	Longest Increasing Subsequence
56	Best Time to Buy and Sell Stock with Cooldown
57	Minimum Height Trees
58	Burst Balloons
59	Super Ugly Number
60	Count of Smaller Numbers After Self
61	Remove Duplicate Letters
62	Maximum Product of Word Lengths
63	Create Maximum Number
64	Wiggle Sort II
65	Power of Three
66	Count of Range Sum
67	Longest Increasing Path in a Matrix
68	Patching Array
69	Verify Preorder Serialization of a Binary Tree
70	Reconstruct Itinerary
71	Palindrome Pairs
72	Flatten Nested List Iterator
73	Reverse Vowels of a String
74	Russian Doll Envelopes
75	Count Numbers with Unique Digits
76	Max Sum of Rectangle No Larger Than K
77	Find K Pairs with Smallest Sums
78	Guess Number Higher or Lower
79	Guess Number Higher or Lower II
80	Combination Sum IV
81	Kth Smallest Element in a Sorted Matrix
82	Insert Delete GetRandom O(1)
83	Linked List Random Node
84	First Unique Character in a String
85	Longest Absolute File Path
86	Find the Difference
87	Perfect Rectangle
88	UTF-8 Validation
89	Decode String
90	Integer Replacement
91	Evaluate Division
92	Nth Digit
93	Binary Watch
94	Remove K Digits
95	Queue Reconstruction by Height
96	Trapping Rain Water II
97	Longest Palindrome
98	Split Array Largest Sum
99	Add Strings
100	Pacific Atlantic Water Flow
101	Maximum XOR of Two Numbers in an Array
102	Number of Boomerangs
103	Find All Numbers Disappeared in an Array
104	Sort Characters By Frequency
105	Repeated Substring Pattern
106	LFU Cache
107	Island Perimeter
108	Ones and Zeroes
109	Heaters
110	Sliding Window Median
111	Magical String
112	License Key Formatting
113	Smallest Good Base
114	Max Consecutive Ones
115	Predict the Winner
116	Reverse Pairs
117	Target Sum
118	Diagonal Traverse
119	Find Mode in Binary Search Tree
120	Next Greater Element II
121	Relative Ranks
122	Freedom Trail
123	Longest Palindromic Subsequence
124	Detect Capital
125	Longest Uncommon Subsequence I
126	Longest Uncommon Subsequence II
127	Longest Word in Dictionary through Deleting
128	Beautiful Arrangement
129	Minimum Absolute Difference in BST
130	Encode and Decode TinyURL
131	Reverse String II
132	01 Matrix
133	Diameter of Binary Tree
134	Student Attendance Record I
135	Student Attendance Record II
136	Subarray Sum Equals K
137	Shortest Unsorted Continuous Subarray
138	Delete Operation for Two Strings
139	Erect the Fence
140	Smallest Range Covering Elements from K Lists
141	Shopping Offers
142	Maximum Average Subarray I
143	Find Duplicate Subtrees
144	Find K Closest Elements
145	Split Array into Consecutive Subsequences
146	Non-decreasing Array
147	Beautiful Arrangement II
148	Kth Smallest Number in Multiplication Table
149	Implement Magic Dictionary
150	Valid Parenthesis String
151	24 Game
152	Redundant Connection
153	Redundant Connection II
154	Repeated String Match
155	Longest Univalue Path
156	Maximum Sum of 3 Non-Overlapping Subarrays
157	Find K-th Smallest Pair Distance
158	Number of Atoms
159	My Calendar I
160	My Calendar II
161	My Calendar III
162	Daily Temperatures
163	Largest Number At Least Twice of Others
164	Shortest Completing Word
165	Open the Lock
166	Cracking the Safe
167	Pyramid Transition Matrix
168	Couples Holding Hands
169	Toeplitz Matrix
170	Number of Matching Subsequences
171	Minimum Swaps To Make Sequences Increasing
172	Backspace String Compare
173	Maximize Distance to Closest Person
174	All Possible Full Binary Trees
175	Fruit Into Baskets
176	Long Pressed Name
177	Unique Email Addresses
178	Knight Dialer
179	Minimum Area Rectangle
180	K Closest Points to Origin
181	Odd Even Jump
182	Shortest Way to Form String
183	Campus Bikes
184	Confusing Number II
185	Video Stitching
186	Stream of Characters
187	Maximum Level Sum of a Binary Tree
188	String Transforms Into Another String
189	Number of Submatrices That Sum to Target
190	Divide Chocolate
191	Delete Nodes And Return Forest
192	Compare Strings by Frequency of the Smallest Character
193	Tiling a Rectangle with the Fewest Squares
194	Count Number of Nice Subarrays