Most common solutions to problems from interviews of high-tier companies.

Solutions to LeetCode & HackerRank problems.

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The repository is constantly updated when Python or SQL solution to the problem found at LeetCode (primarily) or HackerRank is solved. The solutions to LeetCode problems are posted at the discussion sections in each solved problem folder.
If the solved Leetcode problem is one of the problems asked by high-tier companies like Adobe, Airbnb, Amazon, Apple, Bloomberg, DE Shaw, Goldman Sachs, Google with Google Top, LinkedIn, Meta, Microsoft, Netflix, Reddit, Spotify, Tesla, TikTok, Twitter or Uber then that solution of specific company is added to the company's section as my GitHub solution found through contents. Otherwise it is added here as the solved problem is not glued to any of the high-tier companies' section; it is just a random problem that was solved.

The progress of my LeetCode account regarding these solutions with additional information on them can be found by looking at my LeetCode profile.

The Leetcode solutions of Python are found here while HackerRank solutions of Python are found here. Each problem folder has the description of the problem found through pressing the link in README at the respective folder or if it is provided for the particular high-tier company found through contents. By pressing on that company you will be redirected to the problem description (1^st column) followed by the solution implemented in PyCharm (2^nd column).

Currently, doing Python problems of LeetCode. HackerRank problems were finished on May and from 28^th of May 2022 am working on solving at least one Python problem from LeetCode daily. The solution is put at the respective LeetCode folder and added to the list of a high-tier company where it is a common interview question to be asked to solve. The problems for a particular company is seen through contents list.

SQL solutions of problems at HackerRank & LeetCode will come in Fall while they will be updated here for HackerRank and here for LeetCode.

Table of Contents

• Table of contents
• Preparation for Interiews
• Must Do Problems
• Adobe
• Airbnb
• Amazon
• Apple
• Bloomberg
• DE Shaw
• Goldman Sachs
• Google Top
• Google
• LinkedIn
• Meta
• Microsoft
• Netflix
• Reddit
• Spotify
• Tesla
• TikTok
• Twitter
• Uber
• Others

Preparation for Interviews

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To prepare for a MAANG interview or a MAANG-level company interview as well as land a job there I highly recommend solving as many problems below as possible and doing one or all of these:

• Joining Hackpack community
• Solving Top LeetCode Problems
• Honing Python Skills
• Looking at possible Multiple Choice Questions

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Must Do Problems

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

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Adobe

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No.	Questions	Solution in PyCharm
1	Mirror Reflection	Mirror Reflection
2	Merge Two Sorted Lists	Merge Two Sorted Lists
3	Merge k Sorted Lists	Merge k Sorted Lists
4	Best Time to Buy and Sell Stock	Best Time to Buy and Sell Stock
5	Number of 1 Bits	Number of 1 bits
6	Contains Duplicate	Contains Duplicate
7	Missing Number	Missing Number
8	Counting Bits	Counting bits
9	Merge Intervals	Merge Intervals
10	Valid Palindrome	Valid Palindrome
11	Valid Parentheses	Valid Parentheses
12	Climbing Stairs	Climbing Stairs
13	Maximum Depth of Binary Tree	Maximum Depth of Binary Tree
14	Lowest Common Ancestor of a Binary Search Tree	Lowest Common Ancestor of a Binary Search Tree
15	Container With Most Water	Container With Most Water
16	3Sum	3Sum
17	Longest Substring Without Repeating Characters	Longest Substring Without Repeating Characters
18	Longest Palindromic Substring	Longest Palindromic Substring
19	Rotate Image	Rotate Image
20	Search in Rotated Sorted Array	Search in Rotated Sorted Array
21	Word Break	Word Break
22	Number of Islands	Number of Islands
23	Coin Change	Coin Change
24	Maximum Subarray	Maximum Subarray
25	Product of Array Except Self	Product of Array Except Self
26	Minimum Window Substring	Minimum Window Substring
27	Median of Two Sorted Arrays	Median of Two Sorted Arrays
28	Valid Anagram	Valid Anagram
29	Search a 2D Matrix II	Search a 2D Matrix II
30	Sliding Window Maximum	Sliding Window Maximum
31	Lowest Common Ancestor of a Binary Tree	Lowest Common Ancestor of a Binary Tree
32	Maximal Square	Maximal Square
33	Kth Largest Element in an Array	Kth Largest Element in an Array
34	Word Search	Word Search
35	Word Search II	Word Search II
36	Implement Trie (Prefix Tree)	Implement Trie (Prefix Tree)
37	Best Time to Buy and Sell Stock IV	Best Time to Buy and Sell Stock IV
38	Binary Search Tree Iterator	Binary Search Tree Iterator
39	Two Sum II - Input array is sorted	Two Sum II - Input Array Is Sorted
40	Min Stack	Min Stack
41	Find Minimum in Rotated Sorted Array	Find Minimum in Rotated Sorted Array
42	Maximum Product Subarray	Maximum Product Subarray
43	Linked List Cycle	Linked List Cycle
44	Clone Graph	Clone Graph
45	Longest Consecutive Sequence	Longest Consecutive Sequence
46	Word Ladder	Word Ladder
47	Best Time to Buy and Sell Stock	Best Time to Buy and Sell Stock
48	Best Time to Buy and Sell Stock II	Best Time to Buy and Sell Stock II
49	Pascal's Triangle	Pascal's Triangle
50	Reverse Linked List	Reverse Linked List
51	Count Primes	Count Primes
52	House Robber	House Robber
53	Decode Ways	Decode Ways
54	Merge Sorted Array	Merge Sorted Array
55	Subsets	Subsets
56	Set Matrix Zeroes	Set Matrix Zeroes
57	Minimum Path Sum	Minmum Path Sum
58	Unique Paths	Unique Paths
59	Jump Game	Jump Game
60	Spiral Matrix	Spiral Matrix
61	N-Queens	N-Queens
62	Pow(x, n)	Pow(x, n)
63	Group Anagrams	Group Anagrams
64	Permutations	Permutations
65	Trapping Rain Water	Trapping Rain Water
66	Combination Sum	Combination Sum
67	Count and Say	Count and say
68	Valid Sudoku	Valid Sudoku
69	Longest Valid Parentheses	Longest Valid Parentheses
70	Next Permutation	Next Permutation
71	Generate Parentheses	Generate Parentheses
72	Letter Combinations of a Phone Number	Letter Combinations of a Phone Number
73	3Sum Closest	3Sum Closest
74	Roman to Integer	Roman to Integer
75	String to Integer (atoi)	String to Integer (atoi)
76	Longest Substring Without Repeating Characters	Longest Substring Without Repeating Characters
77	Add Two Numbers	Add Two Numbers
78	Two Sum	Two Sum
79	Daily Temperatures	Daily Temperatures
80	Basic Calculator	Basic Calculator
81	Basic Calculator II	Basic Calculator II
82	Lowest Common Ancestor of a Binary Search Tree	Lowest Common Ancestor of a Binary Search Tree
83	Game of Life	Game of Life
84	Regular Expression Matching	Regular Expression Matching
85	Wildcard Matching	Wildvard Matching
86	Single Number	Single Number
87	Happy Number	Happy Number
88	Contains Duplicate II	Contains Duplicate II
89	Contains Duplicate III	Contains Duplicate III
90	Add Strings	Add Strings
99	Reverse Nodes in k-Group	Reverse Nodes in k-Group
100	Sudoku Solver	Sudoku Solver
101	Multiply Strings	Multiply Strings
102	Sort Colors	Sort Colors
103	Course Schedule	Course Schedule
104	Move Zeroes	Move Zeroes
105	Top K Frequent Elements	Top K Frequent Elements
106	Subarray Sum Equals K	Subarray Sum Equals K
107	Maximum Number of Balloons	here
108	Jump Game II	Jump Gmae II.
109	Find All Duplicates in an Array	Find All Duplicates in an Array
110	Reverse Words in a String	Reverse Words in a String
111	Word Pattern	Word Pattern
112	Search a 2D Matrix	Search a 2D Matrix
113	Longest Word in Dictionary	Longest Word in Dictionary
114	Largest Number	Largest Number
115	Invert Binary Tree	Invert Binary Tree
116	Guess Number Higher or Lower	Guess Number Higher or Lower
117	Island Perimeter	Island Perimeter
118	Flood fill	Flood fill
119	Find if Path Exists in Graph	Find if Path Exists in Graph
120	Symmetric Tree	Symmetric Tree

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Airbnb

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No.	Questions	Solution in PyCharm
1	Two Sum	Two Sum
2	Combination Sum	Combination Sum
3	Combination Sum II	Combination Sum II
4	Contains Duplicate	Contains Duplicate
5	Contains Duplicate II	Contains Duplicate II
6	Contains Duplicate III	Contains Duplicate III
7	Minimum Window Substring	Minimum Window Substring
8	Maximal Square	Maximal Square
9	Word Search II	Word Search II
10	Fraction to Recurring Decimal	Fraction to Recurring Decimal
11	House Robber	House Robber
12	Trapping Rain Water	Trapping Rain Water
13	Merge k Sorted Lists	Merge k Sorted Lists
14	Add Two Numbers	Add Two Numbers
15	Median of Two Sorted Arrays	Median of Two Sorted Arrays
16	Regular Expression Matching	Regular Expression Matching
17	Valid Parentheses	Valid Parentheses
18	Search in Rotated Sorted Array	Search in Rotated Sorted Array
19	Wildcard Matching	Wildvard Matching
20	Single Number	Single Number
21	Fraction to Recurring Decimal	Fraction to Recurring Decimal
22	Reverse Bits	Reverse bits.
23	Happy Number	Happy Number
24	Basic Calculator II	Basic Calculator II
25	Alien Dictionary	Alien Dictionary
26	Find Median from Data Stream	Find Median from Data Stream
27	Coin Change	Coin Change
28	Add Strings	Add Strings

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Amazon

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No.	Questions	Solution in PyCharm
1	Two Sum	Two Sum
2	Add Two Numbers	Add Two Numbers
3	String to Integer (atoi)	String to Integer (atoi)
4	Merge Two Sorted Lists	Merge Two Sorted Lists
5	Merge k Sorted Lists	Merge k Sorted Lists
6	Permutations	Permutations
7	Best Time to Buy and Sell Stock	Best Time to Buy and Sell Stock
8	Merge Intervals	Merge Intervals
9	Pascal's Triangle II	Pascal's Triangle II
10	Valid Parentheses	Valid Parentheses
11	Same Tree	Same Tree
12	Linked List Cycle	Linked List Cycle
13	Reverse Linked List	Reverse Linked List
14	Valid Anagram	Valid Anagram
15	Lowest Common Ancestor of a Binary Search Tree	Lowest Common Ancestor of a Binary Search Tree
16	Subtree of Another Tree	Subtree of Another Tree
17	3Sum	3Sum
18	Longest Substring Without Repeating Characters	Longest Substring Without Repeating Characters
19	Longest Palindromic Substring	Longest Palindromic Substring
20	Rotate Image	Rotate Image
21	Word Break	Word Break
22	Number of Islands	Number of Islands
23	Group Anagrams	Group Anagrams
24	Set Matrix Zeroes	Set Matrix Zeroes
25	Product of Array Except Self	Product of Array Except Self
26	Minimum Window Substring	Minimum Window Substring
27	Validate Binary Search Tree	Validate Binary Search Tree
28	Binary Tree Level Order Traversal	Binary Tree Level Order Traversal
29	Serialize and Deserialize BST	Serialize and Deserialize BST
30	Top K Frequent Elements	Top K Frequent Elements
31	Lowest Common Ancestor of a Binary Tree	Lowest Common Ancestor of a Binary Tree
32	Word Search II	Word Search II
33	Find Median from Data Stream	Find Median from Data Stream
34	Subarray Sum Equals K	Subarray Sum Equals K
35	ZigZag Conversion	ZigZag Conversion
36	Kth Largest Element in an Array	Kth Largest Element in an Array
37	Find All Anagrams in a String	Find All Anagrams in a String
38	Basic Calculator	Basic Calculator
39	Letter Combinations of a Phone Number	Letter Combinations of a Phone Number
40	Sort Colors	Sort Colors
41	Generate Parentheses	Generate Parentheses
42	Word Ladder	Word Ladder
43	Edit Distance	Edit Distance
44	Rotate Array	Rotate Array
45	Count Primes	Count Primes
46	Minimum Path Sum	Minmum Path Sum
47	Trapping Rain Water	Trapping Rain Water
48	K Closest Points to Origin	K Closest Points to Origin
49	Subsets	Subsets
50	Happy Number	Happy Number
51	Search a 2D Matrix II	Search a 2D Matrix II
52	Min Stack	Min Stack
53	Spiral Matrix II	Spiral Matrix II
54	Unique Paths II	Unique Paths II
55	Accounts Merge	Accounts Merge
56	Gray Code	Gray Code
57	Word Ladder II	Word Ladder II
58	Third Maximum Number	Third Maximum Number
59	Binary Search Tree Iterator	Binary Search Tree Iterator
60	Median of Two Sorted Arrays	Median of Two Sorted Arrays
61	Two Sum II - Input array is sorted	Two Sum II - Input Array Is Sorted
62	Sliding Window Maximum	Sliding Window Maximum
63	Minesweeper	Minesweeper
64	First Unique Character in a String	First Unique Character in a String
65	Find Pivot Index	Find Pivot Index
66	Solve the Equation	Solve the Equation
67	Combination Sum	Combination Sum
68	Combination Sum II	Combination Sum II
69	Maximum Depth of Binary Tree	Maximum Depth of Binary Tree
70	Container With Most Water	Container With Most Water
71	Search in Rotated Sorted Array	Search in Rotated Sorted Array
72	Word Search	Word Search
73	Coin Change	Coin Change
74	Maximum Subarray	Maximum Subarray
75	Remove All Adjacent Duplicates in String II)	Remove All Adjacent Duplicates in String II
76	High Five	High Five
77	Shortest Word Distance	Shortest Word Distance
78	Maximal Square	Maximal Square
79	Implement Trie (Prefix Tree)	Implement Trie (Prefix Tree)
80	The Skyline Problem	The Skyline Problem
81	Best Time to Buy and Sell Stock II	Best Time to Buy and Sell Stock II
82	Best Time to Buy and Sell Stock IV	Best Time to Buy and Sell Stock IV
83	Fraction to Recurring Decimal	Fraction to Recurring Decimal
84	Find Minimum in Rotated Sorted Array	Find Minimum in Rotated Sorted Array
85	Maximum Product Subarray	Maximum Product Subarray
86	Clone Graph	Clone Graph
87	Longest Consecutive Sequence	Longest Consecutive Sequence
88	Pascal's Triangle	Pascal's Triangle
89	Valid Palindrome	Valid Palindrome
90	House Robber	House Robber
91	Decode Ways	Decode Ways
92	Merge Sorted Array	Merge Sorted Array
93	Climbing Stairs	Climbing Stairs
94	Unique Paths	Unique Paths
95	Insert Interval	Insert Interval
96	Jump Game	Jump Game
97	N-Queens	N-Queens
98	Pow(x, n)	Pow(x, n)
99	Count and Say	Count and say
100	Valid Sudoku	Valid Sudoku
101	Longest Valid Parentheses	Longest Valid Parentheses
102	Next Permutation	Next Permutation
103	Find the Index of the First Occurrence in a String	Find the Index of the First Occurrence in a String
104	3Sum Closest	3Sum Closest
105	Roman to Integer	Roman to Integer
106	Daily Temperatures	Daily Temperatures
107	Game of Life	Game of Life
108	Regular Expression Matching	Regular Expression Matching
109	Wildcard Matching	Wildvard Matching
110	Single Number	Single Number
111	Reverse Bits	Reverse bits.
112	Contains Duplicate II	Contains Duplicate II
113	Contains Duplicate III	Contains Duplicate III
114	Basic Calculator II	Basic Calculator II
115	Alien Dictionary	Alien Dictionary
116	Add Strings	Add Strings
117	Reverse Nodes in k-Group	Reverse Nodes in k-Group
118	Sudoku Solver	Sudoku Solver
119	Multiply Strings	Multiply Strings
120	Course Schedule	Course Schedule
121	Move Zeroes	Move Zeroes
122	Jump Game II	Jump Gmae II.
123	Course Schedule III	Course Schedule III
124	Find All Duplicates in an Array	Find All Duplicates in an Array
125	Excel Sheet Column Title	Excel Sheet Column Title
126	Reverse Words in a String	Reverse Words in a String
127	Word Pattern	Word Pattern
128	Search a 2D Matrix	Search a 2D Matrix
129	Longest Word in Dictionary	Longest Word in Dictionary
130	Largest Number	Largest Number
131	Invert Binary Tree	Invert Binary Tree
132	Guess Number Higher or Lower	Guess Number Higher or Lower
133	Number of Enclaves" can be found	Number of Enclaves" can be found
134	Walls And Gates	Walls And Gates
135	Island Perimeter	Island Perimeter
136	Flood fill	Flood fill
137	Find if Path Exists in Graph	Find if Path Exists in Graph
138	Symmetric Tree	Symmetric Tree

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Apple

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No.	Questions	Solution in PyCharm
1	Two Sum	Two Sum
2	Best Time to Buy and Sell Stock	Best Time to Buy and Sell Stock
3	3Sum	3Sum
4	Longest Substring Without Repeating Characters	Longest Substring Without Repeating Characters
5	Maximum Subarray	Maximum Subarray
6	Add Two Numbers	Add Two Numbers
7	Number of Islands	Number of Islands
8	Move Zeroes	Move Zeroes
9	Valid Parentheses	Valid Parentheses
10	Merge Intervals	Merge Intervals
11	Product of Array Except Self	Product of Array Except Self
12	Decode String	Decode String
13	Longest Palindromic Substring	Longest Palindromic Substring
14	Container With Most Water	Container With Most Water
15	Search in Rotated Sorted Array	Search in Rotated Sorted Array
16	Combination Sum	Combination Sum
17	Rotate Image	Rotate Image
18	Spiral Matrix	Spiral Matrix
19	Unique Paths	Unique Paths
20	Word Break	Word Break
21	Random Pick with Weight	Random Pick with Weight
22	Roman to Integer	Roman to Integer
23	Letter Combinations of a Phone Number	Letter Combinations of a Phone Number
24	Merge k Sorted Lists	Merge k Sorted Lists
25	Pow(x, n)	Pow(x, n)
26	Valid Palindrome	Valid Palindrome
27	House Robber	House Robber
28	First Bad Version	First Bad Version
29	Find Median from Data Stream	Find Median from Data Stream
30	Regular Expression Matching	Regular Expression Matching
31	Merge Two Sorted Lists	Merge Two Sorted Lists
32	Remove Duplicates from Sorted Array	Remove Duplicates from Sorted Array
33	Group Anagrams	Group Anagrams
34	Word Search	Word Search
35	Word Search II	Word Search II
36	Merge Sorted Array	Merge Sorted Array
37	Pascal's Triangle	Pascal's Triangle
38	Maximum Product Subarray	Maximum Product Subarray
39	Count of Smaller Numbers After Self	Count of Smaller Numbers After Self
40	Top K Frequent Elements	Top K Frequent Elements
41	Permutations	Permutations
42	Climbing Stairs	Climbing Stairs
43	Set Matrix Zeroes	Set Matrix Zeroes
44	Maximal Rectangle	Maximal Rectangle
45	Binary Tree Level Order Traversal	Binary Tree Level Order Traversal
46	Maximum Depth of Binary Tree	Maximum Depth of Binary Tree
47	Longest Consecutive Sequence	Longest Consecutive Sequence
48	Course Schedule	Course Schedule
49	Implement Trie (Prefix Tree)	Implement Trie (Prefix Tree)
50	Contains Duplicate	Contains Duplicate
51	Maximal Square	Maximal Square
52	Lowest Common Ancestor of a Binary Tree	Lowest Common Ancestor of a Binary Tree
53	H-Index	H-Index
54	Sort Colors	Sort Colors
55	Generate Parentheses	Generate Parentheses
56	Word Ladder	Word Ladder
57	Rotate Array	Rotate Array
58	Remove Duplicate Letters	Remove Duplicate Letters
59	3Sum Closest	3Sum Closest
60	Valid Parenthesis String	Valid Parenthesis String
61	Count Primes	Count Primes
62	Minimum Path Sum	Minmum Path Sum
63	Valid Sudoku	Valid Sudoku
64	Reverse Integer	Reverse Integer
65	Multiply Strings	Multiply Strings
66	Integer to Roman	Integer to Roman
67	First Missing Positive	First Missing Positive
68	Palindrome Number	Palindrome Number
69	N-Queens	N-Queens
70	Longest Valid Parentheses	Longest Valid Parentheses
71	Largest Rectangle in Histogram	Largest Rectangle in Histogram
72	Word Break II	Word Break II
73	Max Consecutive Ones III	Max Consecutive Ones III
74	Next Greater Element II	Next Greater Element II
75	Find First and Last Position of Element in Sorted Array	Find First and Last Position of Element in Sorted Array
76	Sqrt(x)	Sqrt(x)
77	Integer to English Words	Integer to English Words
78	Majority Element	Majority Element
79	Basic Calculator II	Basic Calculator II
80	Reverse Words in a String III	Reverse Words in a String III
81	4Sum	4Sum
82	Frog Jump	Frog Jumo
83	Happy Number	Happy Number
84	Sudoku Solver	Sudoku Solver
85	Search a 2D Matrix II	Search a 2D Matrix II
86	Min Stack	Min Stack
87	Median of Two Sorted Arrays	Median of Two Sorted Arrays
88	Valid Anagram	Valid Anagram
89	Maximum Depth of Binary Tree	Maximum Depth of Binary Tree
90	Coin Change	Coin Change
91	Remove All Adjacent Duplicates in String II)	Remove All Adjacent Duplicates in String II
92	Sliding Window Maximum	Sliding Window Maximum
93	The Skyline Problem	The Skyline Problem
94	Kth Largest Element in an Array	Kth Largest Element in an Array
95	Best Time to Buy and Sell Stock IV	Best Time to Buy and Sell Stock IV
96	Binary Search Tree Iterator	Binary Search Tree Iterator
97	Two Sum II - Input array is sorted	Two Sum II - Input Array Is Sorted
98	Find Minimum in Rotated Sorted Array	Find Minimum in Rotated Sorted Array
99	Fraction to Recurring Decimal	Fraction to Recurring Decimal
100	Linked List Cycle	Linked List Cycle
101	Clone Graph	Clone Graph
102	Best Time to Buy and Sell Stock II	Best Time to Buy and Sell Stock II
103	Pascal's Triangle	Pascal's Triangle
104	Reverse Linked List	Reverse Linked List
105	Decode Ways	Decode Ways
106	Subsets	Subsets
107	Unique Paths II	Unique Paths II
108	Insert Interval	Insert Interval
109	Jump Game	Jump Game
110	Pow(x, n)	Pow(x, n)
111	Trapping Rain Water	Trapping Rain Water
112	Count and Say	Count and say
113	Next Permutation	Next Permutation
114	Find the Index of the First Occurrence in a String	Find the Index of the First Occurrence in a String
115	String to Integer (atoi)	String to Integer (atoi)
116	Daily Temperatures	Daily Temperatures
117	Basic Calculator	Basic Calculator
118	Basic Calculator II	Basic Calculator II
119	Lowest Common Ancestor of a Binary Search Tree	Lowest Common Ancestor of a Binary Search Tree
120	Game of Life	Game of Life
121	Wildcard Matching	Wildvard Matching
122	Single Number	Single Number
123	Reverse Bits	Reverse bits.
124	Contains Duplicate III	Contains Duplicate III
125	Alien Dictionary	Alien Dictionary
126	Add Strings	Add Strings
127	Reverse Nodes in k-Group	Reverse Nodes in k-Group
128	Subarray Sum Equals K	Subarray Sum Equals K
129	Jump Game II	Jump Gmae II.
130	Find All Duplicates in an Array	Find All Duplicates in an Array
131	Reverse Words in a String	Reverse Words in a String
132	Word Pattern	Word Pattern
133	Search a 2D Matrix	Search a 2D Matrix
134	Check If N and Its Double Exist	Check If N and Its Double Exist
135	Largest Number	Largest Number
136	Invert Binary Tree	Invert Binary Tree
137	Guess Number Higher or Lower	Guess Number Higher or Lower
138	Walls And Gates	Walls And Gates
139	Island Perimeter	Island Perimeter
140	Flood fill	Flood fill
141	Find if Path Exists in Graph	Find if Path Exists in Graph
142	Symmetric Tree	Symmetric Tree

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Bloomberg

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No.	Questions	Solution in PyCharm
1	Mirror Reflection	Mirror Reflection
2	Merge Two Sorted Lists	Merge Two Sorted Lists
3	Merge k Sorted Lists	Merge k Sorted Lists
4	Best Time to Buy and Sell Stock	Best Time to Buy and Sell Stock
5	Number of 1 Bits	Number of 1 bits
6	Contains Duplicate	Contains Duplicate
7	Meeting Rooms	Meeting Rooms.
8	Missing Number	Missing Number
9	Merge Intervals	Merge Intervals
10	Valid Palindrome	Valid Palindrome
11	Valid Parentheses	Valid Parentheses
12	Climbing Stairs	Climbing Stairs
13	Valid Anagram	Valid Anagram
14	Lowest Common Ancestor of a Binary Search Tree	Lowest Common Ancestor of a Binary Search Tree
15	Container With Most Water	Container With Most Water
16	3Sum	3Sum
17	Longest Substring Without Repeating Characters	Longest Substring Without Repeating Characters
18	Longest Palindromic Substring	Longest Palindromic Substring
19	Rotate Image	Rotate Image
20	Search in Rotated Sorted Array	Search in Rotated Sorted Array
21	Word Search	Word Search
22	Word Search II	Word Search II
23	Word Break	Word Break
24	Number of Islands	Number of Islands
25	Coin Change	Coin Change
26	Maximum Subarray	Maximum Subarray
27	Product of Array Except Self	Product of Array Except Self
28	Median of Two Sorted Arrays	Median of Two Sorted Arrays
29	Remove All Adjacent Duplicates in String II)	Remove All Adjacent Duplicates in String II
30	Palindrome Permutation	Palindrome Permutation
31	Search a 2D Matrix II	Search a 2D Matrix II
32	Sliding Window Maximum	Sliding Window Maximum
33	Lowest Common Ancestor of a Binary Tree	Lowest Common Ancestor of a Binary Tree
34	The Skyline Problem	The Skyline Problem
35	Kth Largest Element in an Array	Kth Largest Element in an Array
36	Implement Trie (Prefix Tree)	Implement Trie (Prefix Tree)
37	Best Time to Buy and Sell Stock IV	Best Time to Buy and Sell Stock IV
38	Binary Search Tree Iterator	Binary Search Tree Iterator
39	Two Sum	Two Sum
40	Two Sum II - Input array is sorted	Two Sum II - Input Array Is Sorted
41	Min Stack	Min Stack
42	Find Minimum in Rotated Sorted Array	Find Minimum in Rotated Sorted Array
43	Maximum Product Subarray	Maximum Product Subarray
44	Linked List Cycle	Linked List Cycle
45	Clone Graph	Clone Graph
46	Longest Consecutive Sequence	Longest Consecutive Sequence
47	Word Ladder	Word Ladder
48	Best Time to Buy and Sell Stock II	Best Time to Buy and Sell Stock II
49	Pascal's Triangle	Pascal's Triangle
50	Reverse Linked List	Reverse Linked List
51	House Robber	House Robber
52	Decode Ways	Decode Ways
53	Merge Sorted Array	Merge Sorted Array
54	Subsets	Subsets
55	Set Matrix Zeroes	Set Matrix Zeroes
56	Minimum Path Sum	Minmum Path Sum
57	Unique Paths	Unique Paths
58	Unique Paths II	Unique Paths II
59	Insert Interval	Insert Interval
60	Jump Game	Jump Game
61	Spiral Matrix	Spiral Matrix
62	N-Queens	N-Queens
63	Pow(x, n)	Pow(x, n)
64	Group Anagrams	Group Anagrams
65	Permutations	Permutations
66	Trapping Rain Water	Trapping Rain Water
67	Combination Sum	Combination Sum
68	Count and Say	Count and say
69	Valid Sudoku	Valid Sudoku
70	Next Permutation	Next Permutation
71	Find the Index of the First Occurrence in a String	Find the Index of the First Occurrence in a String
72	Generate Parentheses	Generate Parentheses
73	Letter Combinations of a Phone Number	Letter Combinations of a Phone Number
74	3Sum Closest	3Sum Closest
75	Roman to Integer	Roman to Integer
76	String to Integer (atoi)	String to Integer (atoi)
77	Add Two Numbers	Add Two Numbers
78	Daily Temperatures	Daily Temperatures
79	Game of Life	Game of Life
80	Regular Expression Matching	Regular Expression Matching
81	Wildcard Matching	Wildvard Matching
82	Single Number	Single Number
83	Reverse Bits	Reverse bits.
84	Happy Number	Happy Number
85	Contains Duplicate II	Contains Duplicate II
86	Alien Dictionary	Alien Dictionary
87	Add Strings	Add Strings
88	Reverse Nodes in k-Group	Reverse Nodes in k-Group
89	Sudoku Solver	Sudoku Solver
90	Multiply Strings	Multiply Strings
91	Sort Colors	Sort Colors
92	Course Schedule	Course Schedule
93	Move Zeroes	Move Zeroes
94	Top K Frequent Elements	Top K Frequent Elements
95	Subarray Sum Equals K	Subarray Sum Equals K
96	Jump Game II	Jump Gmae II.
97	Course Schedule III	Course Schedule III
98	Find All Duplicates in an Array	Find All Duplicates in an Array
99	Reverse Words in a String	Reverse Words in a String
100	Search a 2D Matrix	Search a 2D Matrix
101	Largest Number	Largest Number
102	Invert Binary Tree	Invert Binary Tree
103	Guess Number Higher or Lower	Guess Number Higher or Lower
104	Walls And Gates	Walls And Gates
105	Island Perimeter	Island Perimeter
106	Flood fill	Flood fill
107	Symmetric Tree	Symmetric Tree

---

DE Shaw

(Back to top)

No.	Questions	Solution in PyCharm
1	Maximum Subarray	Maximum Subarray
2	Product of Array Except Self	Product of Array Except Self
3	Daily Temperatures	Daily Temperatures
4	Best Time to Buy and Sell Stock	Best Time to Buy and Sell Stock
5	Best Time to Buy and Sell Stock II	Best Time to Buy and Sell Stock II
6	Max Consecutive Ones III	Max Consecutive Ones III
7	Verifying an Alien Dictionary	Verifying an Alien Dictionary
8	Longest Increasing Path in a Matrix	Longest Increasing Path in a Matrix
9	Sliding Window Maximum	Sliding Window Maximum
10	Number of Islands	Number of Islands
11	Group Anagrams	Group Anagrams
12	Rotate Image	Rotate Image
13	Trapping Rain Water	Trapping Rain Water
14	First Missing Positive	First Missing Positive
15	Next Permutation	Next Permutation
16	Letter Combinations of a Phone Number	Letter Combinations of a Phone Number
17	Container With Most Water	Container With Most Water

---

Goldman Sachs

(Back to top)

No.	Questions	Solution in PyCharm
1	Two Sum	Two Sum
2	Best Time to Buy and Sell Stock	Best Time to Buy and Sell Stock
3	Best Time to Buy and Sell Stock II	Best Time to Buy and Sell Stock II
4	Counting Bits	Counting bits
5	Valid Parentheses	Valid Parentheses
6	Valid Anagram	Valid Anagram
7	3Sum	3Sum
8	Longest Substring Without Repeating Characters	Longest Substring Without Repeating Characters
9	Longest Palindromic Substring	Longest Palindromic Substring
10	Median of Two Sorted Arrays	Median of Two Sorted Arrays
11	Remove All Adjacent Duplicates in String II)	Remove All Adjacent Duplicates in String II
12	Maximum Subarray	Maximum Subarray
13	Product of Array Except Self	Product of Array Except Self
14	Daily Temperatures	Daily Temperatures
15	Number of Islands	Number of Islands
16	Sliding Window Maximum	Sliding Window Maximum
17	Group Anagrams	Group Anagrams
18	Trapping Rain Water	Trapping Rain Water
19	Next Permutation	Next Permutation
20	Letter Combinations of a Phone Number	Letter Combinations of a Phone Number
21	Container With Most Water	Container With Most Water
22	High Five	High Five
23	Palindrome Permutation	Palindrome Permutation
24	Find Pivot Index	Find Pivot Index
25	Palindromic Substrings	Palindromic Substrings
26	Find All Anagrams in a String	Find All Anagrams in a String
27	Pacific Atlantic Water Flow	Pacific Atlantic Water Flow
28	Evaluate Division	Evaluate Division
29	Decode String	Decode String
30	Pascal's Triangle	Pascal's Triangle
31	Counting Bits	Counting bits
32	Coin Change	Coin Change
33	Find Median from Data Stream	Find Median from Data Stream
34	Find the Duplicate Number	Find the Duplicate Number
35	Move Zeroes	Move Zeroes
36	First Bad Version	First Bad Version
37	H-Index	H-Index
38	Meeting Rooms II	Meeting Rooms II
39	Shortest Word Distance	Shortest Word Distance
40	Search a 2D Matrix II	Search a 2D Matrix II
41	Lowest Common Ancestor of a Binary Tree	Lowest Common Ancestor of a Binary Tree
42	Maximal Square	Maximal Square
43	The Skyline Problem	The Skyline Problem
44	Kth Largest Element in an Array	Kth Largest Element in an Array
45	Word Search	Word Search
46	Word Search II	Word Search II
47	Implement Trie (Prefix Tree)	Implement Trie (Prefix Tree)
48	Best Time to Buy and Sell Stock IV	Best Time to Buy and Sell Stock IV
49	Binary Search Tree Iterator	Binary Search Tree Iterator
50	Two Sum II - Input array is sorted	Two Sum II - Input Array Is Sorted
51	Fraction to Recurring Decimal	Fraction to Recurring Decimal
52	Min Stack	Min Stack
53	Find Minimum in Rotated Sorted Array	Find Minimum in Rotated Sorted Array
54	Maximum Product Subarray	Maximum Product Subarray
55	Linked List Cycle	Linked List Cycle
56	Word Break	Word Break
57	Clone Graph	Clone Graph
58	Longest Consecutive Sequence	Longest Consecutive Sequence
59	Word Ladder	Word Ladder
60	Pascal's Triangle	Pascal's Triangle
61	Pascal's Triangle II	Pascal's Triangle II
62	Valid Palindrome	Valid Palindrome
63	Reverse Linked List	Reverse Linked List
64	Count Primes	Count Primes
65	House Robber	House Robber
66	Decode Ways	Decode Ways
67	Merge Sorted Array	Merge Sorted Array
68	Subsets	Subsets
69	Set Matrix Zeroes	Set Matrix Zeroes
70	Climbing Stairs	Climbing Stairs
71	Minimum Path Sum	Minmum Path Sum
72	Unique Paths	Unique Paths
73	Unique Paths II	Unique Paths II
74	Insert Interval	Insert Interval
75	Merge Intervals	Merge Intervals
76	Jump Game	Jump Game
77	Spiral Matrix	Spiral Matrix
78	N-Queens	N-Queens
79	Group Anagrams	Group Anagrams
80	Permutations	Permutations
81	Combination Sum	Combination Sum
82	Count and Say	Count and say
83	Valid Sudoku	Valid Sudoku
84	Search in Rotated Sorted Array	Search in Rotated Sorted Array
85	Longest Valid Parentheses	Longest Valid Parentheses
86	Find the Index of the First Occurrence in a String	Find the Index of the First Occurrence in a String
87	Merge k Sorted Lists	Merge k Sorted Lists
90	Generate Parentheses	Generate Parentheses
91	3Sum Closest	3Sum Closest
92	Roman to Integer	Roman to Integer
93	String to Integer (atoi)	String to Integer (atoi)
94	Add Two Numbers	Add Two Numbers
95	Jump Game II	Jump Gmae II.
96	Search a 2D Matrix	Search a 2D Matrix
97	Longest Word in Dictionary	Longest Word in Dictionary
98	Determine if Two Events Have Conflict	Determine if Two Events Have Conflict
99	Largest Number	Largest Number
100	Invert Binary Tree	Invert Binary Tree
101	Symmetric Tree	Symmetric Tree

---

Google Top

(Back to top)

No.	Questions	Solution in PyCharm
1	Two Sum	Two Sum
2	Maximal Rectangle	Maximal Rectangle
3	Insert Interval	Insert Interval
4	X of a Kind in a Deck of Cards	X of a Kind in a Deck of Cards
5	Maximal Square	Maximal Square
6	Bulls and Cows	Bulls and Cows
7	Evaluate Division	Evaluate Division
8	Decode String	Decode String
9	Longest String Chain	Longest String Chain
10	Validate Stack Sequences	Validate Stack Sequences
11	Minimum Window Substring	Minimum Window Substring
12	The Skyline Problem	The Skyline Problem
13	Longest Increasing Path in a Matrix	Longest Increasing Path in a Matrix
14	Find Median from Data Stream	Find Median from Data Stream
15	Count of Smaller Numbers After Self	Count of Smaller Numbers After Self
16	Network Delay Time	Network Delay Time
17	Subarray Sum Equals K	Subarray Sum Equals K
18	Max Sum of Rectangle No Larger Than K	[Max Sum of Rectangle No Larger Than K
19	Split Array into Consecutive Subsequences	Split Array into Consecutive Subsequences
20	Split Array Largest Sum	Split Array Largest Sum
21	Minimum Domino Rotations For Equal Row	Minimum Domino Rotations For Equal Row
22	Random Pick with Weight	Random Pick with Weight

Google

(Back to top)

No.	Questions	Solution in PyCharm
1	Two Sum	Two Sum
2	Merge k Sorted Lists	Merge k Sorted Lists
3	Remove Duplicates from Sorted Array	Remove Duplicates from Sorted Array
4	Next Permutation	Next Permutation
5	Maximal Rectangle	Maximal Rectangle
6	Move Zeroes	Move Zeroes
7	Merge Intervals	Merge Intervals
8	Insert Interval	Insert Interval
9	Pascal's Triangle	Pascal's Triangle
10	Valid Parentheses	Valid Parentheses
11	Same Tree	Same Tree
12	Plus One	Plus One
13	Bulls and Cows	Bulls and Cows
14	Evaluate Division	Evaluate Division
15	Decode String	Decode String
16	Word Break	Word Break
17	Number of Islands	Number of Islands
18	House Robber	House Robber
19	Longest Consecutive Sequence	Longest Consecutive Sequence
20	Spiral Matrix	Spiral Matrix
21	Product of Array Except Self	Product of Array Except Self
22	Clone Graph	Clone Graph
23	Kth Smallest Element in a BST	Kth Smallest Element in a BST
24	Longest Increasing Subsequence	Longest Increasing Subsequence
25	Pacific Atlantic Water Flow	Pacific Atlantic Water Flow
26	Implement Trie (Prefix Tree)	Implement Trie (Prefix Tree)
27	Word Search II	Word Search II
28	The Skyline Problem	The Skyline Problem
29	Pow(x, n)	Pow(x, n)
30	Longest Increasing Path in a Matrix	Longest Increasing Path in a Matrix
31	Find Median from Data Stream	Find Median from Data Stream
32	Count of Smaller Numbers After Self	Count of Smaller Numbers After Self
33	Subarray Sum Equals K	Subarray Sum Equals K
34	Max Sum of Rectangle No Larger Than K	[Max Sum of Rectangle No Larger Than K
35	Split Array into Consecutive Subsequences	Split Array into Consecutive Subsequences
36	Split Array Largest Sum	Split Array Largest Sum
37	Target Sum	Target Sum
38	H-Index	H-Index
39	Regular Expression Matching	Regular Expression Matching
40	Basic Calculator	Basic Calculator
41	Letter Combinations of a Phone Number	Letter Combinations of a Phone Number
42	Wildcard Matching	Wildvard Matching
43	Add Strings	Add Strings
44	Generate Parentheses	Generate Parentheses
45	Word Ladder	Word Ladder
46	Shortest Palindrome	Shortest Palindrome
47	Remove Duplicate Letters	Remove Duplicate Letters
48	Valid Parenthesis String	Valid Parenthesis String
49	Game of Life	Game of Life
50	Trapping Rain Water	Trapping Rain Water
51	Word Break II	Word Break II
52	Next Greater Element II	Next Greater Element II
53	K Closest Points to Origin	K Closest Points to Origin
54	Expression Add Operators	Expression Add Operators
55	Search a 2D Matrix II	Search a 2D Matrix II
56	Combination Sum IV	Combination Sum IV
57	Min Stack	Min Stack
58	Fraction to Recurring Decimal	Fraction to Recurring Decimal
59	Binary Search Tree Iterator	Binary Search Tree Iterator
60	Perfect Squares	Perfect Squares
61	Find the Difference	Find the Difference
62	Daily Temperatures	Daily Temperatures
63	Isomorphic Strings	Isomorphic Strings
64	Max Consecutive Ones	Max Concsecutive Ones
65	Median of Two Sorted Arrays	Median of Two Sorted Arrays
66	Sliding Window Maximum	Sliding Window Maximum
67	First Unique Character in a String	First Unique Character in a String
68	Maximum Depth of Binary Tree	Maximum Depth of Binary Tree
69	Valid Anagram	Valid Anagram
70	Container With Most Water	Container With Most Water
71	Longest Substring Without Repeating Characters	Longest Substring Without Repeating Characters
72	Longest Palindromic Substring	Longest Palindromic Substring
73	Search in Rotated Sorted Array	Search in Rotated Sorted Array
74	Word Search	Word Search
75	Coin Change	Coin Change
76	Maximum Subarray	Maximum Subarray
77	Palindrome Permutation	Palindrome Permutation
78	Lowest Common Ancestor of a Binary Tree	Lowest Common Ancestor of a Binary Tree
79	Kth Largest Element in an Array	Kth Largest Element in an Array
80	Best Time to Buy and Sell Stock IV	Best Time to Buy and Sell Stock IV
81	Best Time to Buy and Sell Stock II	Best Time to Buy and Sell Stock II
82	Two Sum II - Input array is sorted	Two Sum II - Input Array Is Sorted
83	Find Minimum in Rotated Sorted Array	Find Minimum in Rotated Sorted Array
84	Maximum Product Subarray	Maximum Product Subarray
85	Linked List Cycle	Linked List Cycle
86	Pascal's Triangle	Pascal's Triangle
87	Valid Palindrome	Valid Palindrome
88	Reverse Linked List	Reverse Linked List
89	Decode Ways	Decode Ways
90	Merge Sorted Array	Merge Sorted Array
91	Subsets	Subsets
92	Set Matrix Zeroes	Set Matrix Zeroes
93	Climbing Stairs	Climbing Stairs
94	Minimum Path Sum	Minmum Path Sum
95	Unique Paths	Unique Paths
96	Unique Paths II	Unique Paths II
97	Jump Game	Jump Game
98	N-Queens	N-Queens
99	Group Anagrams	Group Anagrams
100	Permutations	Permutations
101	Count and Say	Count and say
102	Combination Sum	Combination Sum
103	Valid Sudoku	Valid Sudoku
104	Longest Valid Parentheses	Longest Valid Parentheses
105	Find the Index of the First Occurrence in a String	Find the Index of the First Occurrence in a String
106	3Sum	3Sum
107	3Sum Closest	3Sum Closest
108	Roman to Integer	Roman to Integer
109	String to Integer (atoi)	String to Integer (atoi)
110	Add Two Numbers	Add Two Numbers
111	Lowest Common Ancestor of a Binary Search Tree	Lowest Common Ancestor of a Binary Search Tree
112	Single Number	Single Number
113	Reverse Bits	Reverse bits.
114	Happy Number	Happy Number
115	Contains Duplicate II	Contains Duplicate II
116	Contains Duplicate III	Contains Duplicate III
117	Basic Calculator II	Basic Calculator II
118	Alien Dictionary	Alien Dictionary
119	Reverse Nodes in k-Group	Reverse Nodes in k-Group
120	Sudoku Solver	Sudoku Solver
121	Multiply Strings	Multiply Strings
122	Sort Colors	Sort Colors
123	Course Schedule	Course Schedule
124	Top K Frequent Elements	Top K Frequent Elements
125	Perfect Rectangle	Perfect Rectangle
126	Jump Game II	Jump Gmae II
127	Course Schedule III	Course Schedule III
128	Permutations II	Permutations II
129	Find All Duplicates in an Array	Find All Duplicates in an Array
130	Excel Sheet Column Title	Excel Sheet Column Title
131	Reverse Words in a String	Reverse Words in a String
132	Strobogrammatic Number	Strobogrammatic Number
133	Search a 2D Matrix	Search a 2D Matrix
134	Check If N and Its Double Exist	Check If N and Its Double Exist
135	Longest Word in Dictionary	Longest Word in Dictionary
136	Determine if Two Events Have Conflict	Determine if Two Events Have Conflict
137	Largest Number	Largest Number
138	Invert Binary Tree	Invert Binary Tree
139	Guess Number Higher or Lower	Guess Number Higher or Lower
140	Number of Enclaves" can be found	Number of Enclaves" can be found
141	Walls And Gates	Walls And Gates
142	Island Perimeter	Island Perimeter
143	Flood fill	Flood fill
144	Find if Path Exists in Graph	Find if Path Exists in Graph
145	Tree Diameter	Tree Diameter
146	Symmetric Tree	Symmetric Tree

---

LinkedIn

(Back to top)

No.	Questions	Solution in PyCharm
1	Number of Islands	Number of Islands
2	Valid Number	Valid Number
3	Paint House	Paint House
4	Valid Palindrome	Valid Palindrome
5	Valid Parentheses	Valid Parentheses
6	Same Tree	Same Tree
7	Maximum Depth of Binary Tree	Maximum Depth of Binary Tree
8	Lowest Common Ancestor of a Binary Search Tree	Lowest Common Ancestor of a Binary Search Tree
9	Search in Rotated Sorted Array	Search in Rotated Sorted Array
10	Maximum Subarray	Maximum Subarray
11	Minimum Window Substring	Minimum Window Substring
12	Shortest Word Distance	Shortest Word Distance
13	Lowest Common Ancestor of a Binary Tree	Lowest Common Ancestor of a Binary Tree
14	Kth Largest Element in an Array	Kth Largest Element in an Array
15	Binary Search Tree Iterator	Binary Search Tree Iterator
16	Maximum Product Subarray	Maximum Product Subarray
17	Word Break	Word Break
18	Longest Consecutive Sequence	Longest Consecutive Sequence
19	Word Ladder	Word Ladder
20	House Robber	House Robber
21	Merge Sorted Array	Merge Sorted Array
22	Climbing Stairs	Climbing Stairs
23	Insert Interval	Insert Interval
24	Merge Intervals	Merge Intervals
25	Pow(x, n)	Pow(x, n)
26	Median of Two Sorted Arrays	Median of Two Sorted Arrays
27	Permutations	Permutations
28	Combination Sum	Combination Sum
29	Merge k Sorted Lists	Merge k Sorted Lists
30	Letter Combinations of a Phone Number	Letter Combinations of a Phone Number
31	3Sum	3Sum
32	Roman to Integer	Roman to Integer
33	String to Integer (atoi)	String to Integer (atoi)
34	Two Sum	Two Sum
35	Basic Calculator	Basic Calculator
36	Basic Calculator II	Basic Calculator II
37	Top K Frequent Elements	Top K Frequent Elements
38	Subarray Sum Equals K	Subarray Sum Equals K
39	Reverse Words in a String	Reverse Words in a String
40	Invert Binary Tree	Invert Binary Tree
41	Symmetric Tree	Symmetric Tree

---

Meta

(Back to top)

No.	Questions	Solution in PyCharm
1	Merge k Sorted Lists	Merge k Sorted Lists
2	Remove Duplicates from Sorted Array	Remove Duplicates from Sorted Array
3	Interval List Intersections	Interval List Intersections
4	Merge Sorted Array	Merge Sorted Array
5	Best Time to Buy and Sell Stock	Best Time to Buy and Sell Stock
6	Best Time to Buy and Sell Stock III	Best Time to Buy and Sell Stock III
7	Best Time to Buy and Sell Stock IV	Best Time to Buy and Sell Stock IV
8	Move Zeroes	Move Zeroes
9	Roman to Integer	Roman to Integer
10	Merge Intervals	Merge Intervals
11	Insert Interval	Insert Interval
12	Valid Palindrome II	Valid Palindrome II
13	Valid Parentheses	Valid Parentheses
14	Plus One	Plus One
15	Maximal Square	Maximal Square
16	3Sum	3Sum
17	Search in Rotated Sorted Array	Search in Rotated Sorted Array
18	Word Break	Word Break
19	Number of Islands	Number of Islands
20	Course Schedule	Course Schedule
21	Maximum Subarray	Maximum Subarray
22	Longest Consecutive Sequence	Longest Consecutive Sequence
23	Product of Array Except Self	Product of Array Except Self
24	Minimum Window Substring	Minimum Window Substring
25	Binary Tree Level Order Traversal	Binary Tree Level Order Traversal
26	Clone Graph	Clone Graph
27	Kth Smallest Element in a BST	Kth Smallest Element in a BST
28	Encode and Decode Strings	Encode and Decode Strings
29	Design Add and Search Words Data Structure	Design Add and Search Words Data Structure
30	Lowest Common Ancestor of a Binary Tree	Lowest Common Ancestor of a Binary Tree
31	Implement Trie (Prefix Tree)	Implement Trie (Prefix Tree)
32	Binary Tree Maximum Path Sum	Binary Tree Maximum Path Sum
33	The Skyline Problem	The Skyline Problem
34	Pow(x, n)	Pow(x, n)
35	Longest Increasing Path in a Matrix	Longest Increasing Path in a Matrix
36	Subarray Sum Equals K	Subarray Sum Equals K
37	Valid Palindrome	Valid Palindrome
38	Target Sum	Target Sum
39	H-Index	H-Index
40	Count and Say	Count and say
41	Task Scheduler	Task Scheduler
42	Regular Expression Matching	Regular Expression Matching
43	Simplify Path	Simplify Path
44	Kth Largest Element in an Array	Kth Largest Element in an Array
45	Find All Anagrams in a String	Find All Anagrams in a String
46	Custom Sort String	Custom Sort String
47	Letter Combinations of a Phone Number	Letter Combinations of a Phone Number
48	Wildcard Matching	Wildvard Matching
49	Add Strings	Add Strings
50	First Bad Version	First Bad Version
51	Is Graph Bipartite?	Is Graph Bipartite?
52	Max Consecutive Ones III	Max Consecutive Ones III
53	K Closest Points to Origin	K Closest Points to Origin
54	Expression Add Operators	Expression Add Operators
55	Sudoku Solver	Sudoku Solver
56	Combination Sum	Combination Sum
57	Combination Sum IV	Combination Sum IV
58	Valid Number	Valid Number
59	Remove Invalid Parentheses	Remove Invalid Parentheses
60	Fraction to Recurring Decimal	Fraction to Recurring Decimal
61	Add Binary	Add Binary
62	Partition Equal Subset Sum	Partition Equal Subset Sum
63	Reverse Nodes in k-Group	Reverse Nodes in k-Group
64	Find the Index of the First Occurrence in a String	Find the Index of the First Occurrence in a String
65	Binary Search Tree Iterator	Binary Search Tree Iterator
66	Verifying an Alien Dictionary	Verifying an Alien Dictionary
67	Shortest Bridge	Shortest Bridge
68	Continuous Subarray Sum	Continuous Subarray Sum
69	Minimum Remove to Make Valid Parentheses	Minimum Remove to Make Valid Parentheses
70	Maximum Depth of Binary Tree	Maximum Depth of Binary Tree
71	Rotate Image	Rotate Image
72	Median of Two Sorted Arrays	Median of Two Sorted Arrays
73	Palindrome Permutation	Palindrome Permutation
74	Shortest Word Distance	Shortest Word Distance
75	Search a 2D Matrix II	Search a 2D Matrix II
76	Sliding Window Maximum	Sliding Window Maximum
77	Word Search	Word Search
78	Word Search II	Word Search II
79	Two Sum	Two Sum
80	Two Sum II - Input array is sorted	Two Sum II - Input Array Is Sorted
81	Min Stack	Min Stack
82	Find Minimum in Rotated Sorted Array	Find Minimum in Rotated Sorted Array
83	Maximum Product Subarray	Maximum Product Subarray
84	Linked List Cycle	Linked List Cycle
85	Word Ladder	Word Ladder
86	Pascal's Triangle	Pascal's Triangle
87	Reverse Linked List	Reverse Linked List
88	House Robber	House Robber
89	Decode Ways	Decode Ways
90	Subsets	Subsets
91	Set Matrix Zeroes	Set Matrix Zeroes
92	Climbing Stairs	Climbing Stairs
93	Unique Paths	Unique Paths
94	Unique Paths II	Unique Paths II
95	Jump Game	Jump Game
96	Spiral Matrix	Spiral Matrix
97	N-Queens	N-Queens
98	Group Anagrams	Group Anagrams
99	Permutations	Permutations
100	Trapping Rain Water	Trapping Rain Water
101	Valid Sudoku	Valid Sudoku
102	Longest Valid Parentheses	Longest Valid Parentheses
103	Next Permutation	Next Permutation
104	Generate Parentheses	Generate Parentheses
105	Longest Palindromic Substring	Longest Palindromic Substring
106	Longest Substring Without Repeating Characters	Longest Substring Without Repeating Characters
107	Add Two Numbers	Add Two Numbers
108	Daily Temperatures	Daily Temperatures
109	Basic Calculator	Basic Calculator
110	Single Number	Single Number
111	Reverse Bits	Reverse bits.
112	Happy Number	Happy Number
113	Contains Duplicate II	Contains Duplicate II
114	Basic Calculator II	Basic Calculator II
115	Alien Dictionary	Alien Dictionary
116	Reverse Nodes in k-Group	Reverse Nodes in k-Group
117	Multiply Strings	Multiply Strings
118	Sort Colors	Sort Colors
119	Top K Frequent Elements	Top K Frequent Elements
120	Find All Duplicates in an Array	Find All Duplicates in an Array
121	Excel Sheet Column Title	Excel Sheet Column Title
122	Reverse Words in a String	Reverse Words in a String
123	Strobogrammatic Number	Strobogrammatic Number
124	Word Pattern	Word Pattern
125	Search a 2D Matrix	Search a 2D Matrix
126	Largest Number	Largest Number
127	Invert Binary Tree	Invert Binary Tree
128	Walls And Gates	Walls And Gates
129	Island Perimeter	Island Perimeter
130	Flood fill	Flood fill
131	Tree Diameter	Tree Diameter
132	Symmetric Tree	Symmetric Tree

---

Microsoft

(Back to top)

No.	Questions	Solution in PyCharm
1	Two Sum	Two Sum
2	Add Two Numbers	Add Two Numbers
3	String to Integer (atoi)	String to Integer (atoi)
4	Roman to Integer	Roman to Integer
5	Merge Two Sorted Lists	Merge Two Sorted Lists
6	Merge k Sorted Lists	Merge k Sorted Lists
7	Number of 1 Bits	Number of 1 bits
8	Missing Number	Missing Number
9	Remove Duplicates from Sorted Array	Remove Duplicates from Sorted Array
10	Merge Intervals	Merge Intervals
11	Valid Palindrome	Valid Palindrome
12	Valid Parentheses	Valid Parentheses
13	Linked List Cycle	Linked List Cycle
14	Reverse Linked List	Reverse Linked List
15	3Sum	3Sum
16	Longest Palindromic Substring	Longest Palindromic Substring
17	Search in Rotated Sorted Array	Search in Rotated Sorted Array
18	Number of Islands	Number of Islands
19	Maximum Subarray	Maximum Subarray
20	Find Minimum in Rotated Sorted Array	Find Minimum in Rotated Sorted Array
21	Spiral Matrix	Spiral Matrix
22	Product of Array Except Self	Product of Array Except Self
23	Jump Game	Jump Game
24	Implement Trie (Prefix Tree)	Implement Trie (Prefix Tree)
25	Word Search II	Word Search II
26	Binary Tree Maximum Path Sum	Binary Tree Maximum Path Sum
27	The Skyline Problem	The Skyline Problem
28	Rotate Array	Rotate Array
29	Reverse Nodes in k-Group	Reverse Nodes in k-Group
30	Binary Search Tree Iterator	Binary Search Tree Iterator
31	Add Digits	Add Digits
32	Median of Two Sorted Arrays	Median of Two Sorted Arrays
33	Kth Largest Element in an Array	Kth Largest Element in an Array
34	Valid Anagram	Valid Anagram
35	Container With Most Water	Container With Most Water
36	Longest Substring Without Repeating Characters	Longest Substring Without Repeating Characters
37	Rotate Image	Rotate Image
38	Word Search	Word Search
39	Word Break	Word Break
40	Coin Change	Coin Change
41	Palindrome Permutation	Palindrome Permutation
42	Search a 2D Matrix II	Search a 2D Matrix II
43	Lowest Common Ancestor of a Binary Tree	Lowest Common Ancestor of a Binary Tree
44	Sliding Window Maximum	Sliding Window Maximum
45	Maximal Square	Maximal Square
46	Two Sum II - Input array is sorted	Two Sum II - Input Array Is Sorted
47	Fraction to Recurring Decimal	Fraction to Recurring Decimal
48	Min Stack	Min Stack
49	Find Minimum in Rotated Sorted Array	Find Minimum in Rotated Sorted Array
50	Maximum Product Subarray	Maximum Product Subarray
51	Clone Graph	Clone Graph
52	Best Time to Buy and Sell Stock	Best Time to Buy and Sell Stock
53	Longest Consecutive Sequence	Longest Consecutive Sequence
54	Pascal's Triangle	Pascal's Triangle
55	Pascal's Triangle II	Pascal's Triangle II
56	Count Primes	Count Primes
57	House Robber	House Robber
58	Merge Sorted Array	Merge Sorted Array
59	Decode Ways	Decode Ways
60	Subsets	Subsets
61	Set Matrix Zeroes	Set Matrix Zeroes
62	Climbing Stairs	Climbing Stairs
63	Minimum Path Sum	Minmum Path Sum
64	Unique Paths	Unique Paths
65	Unique Paths II	Unique Paths II
66	Insert Interval	Insert Interval
67	N-Queens	N-Queens
68	Pow(x, n)	Pow(x, n)
69	Group Anagrams	Group Anagrams
70	Combination Sum	Combination Sum
71	Count and Say	Count and say
72	Valid Sudoku	Valid Sudoku
73	Longest Valid Parentheses	Longest Valid Parentheses
74	Next Permutation	Next Permutation
75	Find the Index of the First Occurrence in a String	Find the Index of the First Occurrence in a String
76	Letter Combinations of a Phone Number	Letter Combinations of a Phone Number
77	3Sum Closest	3Sum Closest
78	Daily Temperatures	Daily Temperatures
79	Game of Life	Game of Life
80	Regular Expression Matching	Regular Expression Matching
81	Wildcard Matching	Wildvard Matching
82	Single Number	Single Number
83	Reverse Bits	Reverse bits.
84	Happy Number	Happy Number
85	Contains Duplicate II	Contains Duplicate II
86	Basic Calculator II	Basic Calculator II
87	Alien Dictionary	Alien Dictionary
88	Add Strings	Add Strings
89	Sudoku Solver	Sudoku Solver
90	Multiply Strings	Multiply Strings
91	Sort Colors	Sort Colors
92	Course Schedule	Course Schedule
93	Move Zeroes	Move Zeroes
94	Top K Frequent Elements	Top K Frequent Elements
95	Subarray Sum Equals K	Subarray Sum Equals K
96	Maximum Number of Balloons	here
97	Jump Game II	Jump Gmae II.
98	Course Schedule III	Course Schedule III
99	Find All Duplicates in an Array	Find All Duplicates in an Array
100	Excel Sheet Column Title	Excel Sheet Column Title
101	Reverse Words in a String	Reverse Words in a String
102	Strobogrammatic Number	Strobogrammatic Number
103	Word Pattern	Word Pattern
104	Search a 2D Matrix	Search a 2D Matrix
105	Largest Number	Largest Number
106	Invert Binary Tree	Invert Binary Tree
107	Walls And Gates	Walls And Gates
108	Find if Path Exists in Graph	Find if Path Exists in Graph
109	Tree Diameter	Tree Diameter
110	Symmetric Tree	Symmetric Tree

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Netflix

(Back to top)

No.	Questions	Solution in PyCharm
1	Department Top Three Salaries	Department Top Three Salaries
2	LRU Cache
3	Valid Parentheses	Valid Parentheses
4	Best Time to Buy and Sell Stock	Best Time to Buy and Sell Stock
5	Merge Intervals	Merge Intervals
6	Group Anagrams	Group Anagrams
7	Top K Frequent Elements	Top K Frequent Elements

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Reddit

(Back to top)

No.	Questions	Solution in PyCharm
1	Combination Sum	Combination Sum
2	Combination Sum II	Combination Sum II
3	Number of Islands	Number of Islands
4	Merge Sorted Array	Merge Sorted Array
5	Subsets	Subsets
6	Insert Interval	Insert Interval
7	Daily Temperatures	Daily Temperatures
8	Merge Intervals	Merge Intervals
9	Best Time to Buy and Sell Stock	Best Time to Buy and Sell Stock
10	Basic Calculator	Basic Calculator
11	Lowest Common Ancestor of a Binary Tree	Lowest Common Ancestor of a Binary Tree
12	Lowest Common Ancestor of a Binary Search Tree	Lowest Common Ancestor of a Binary Search Tree
13	Game of Life	Game of Life

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Spotify

(Back to top)

No.	Questions	Solution in PyCharm
1	Two Sum	Two Sum
2	Valid Palindrome	Valid Palindrome
3	Valid Parentheses	Valid Parentheses
4	Valid Anagram	Valid Anagram
5	Longest Substring Without Repeating Characters	Longest Substring Without Repeating Characters
6	Minimum Window Substring	Minimum Window Substring
7	Daily Temperatures	Daily Temperatures
8	Find Median from Data Stream	Find Median from Data Stream
9	Remove All Adjacent Duplicates in String II)	Remove All Adjacent Duplicates in String II
10	Lowest Common Ancestor of a Binary Tree	Lowest Common Ancestor of a Binary Tree
11	Lowest Common Ancestor of a Binary Search Tree	Lowest Common Ancestor of a Binary Search Tree
12	Kth Largest Element in an Array	Kth Largest Element in an Array
13	Word Search II	Word Search II
14	Linked List Cycle	Linked List Cycle
15	Longest Consecutive Sequence	Longest Consecutive Sequence
16	Maximum Depth of Binary Tree	Maximum Depth of Binary Tree
17	Minimum Window Substring	Minimum Window Substring
18	Sort Colors	Sort Colors
19	Plus One	Plus One
20	Generate Parentheses	Generate Parentheses
21	Walls And Gates	Walls And Gates

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Tesla

(Back to top)

No.	Questions	Solution in PyCharm
1	Two Sum	Two Sum
2	Valid Parentheses	Valid Parentheses
3	Letter Combinations of a Phone Number	Letter Combinations of a Phone Number
4	3Sum	3Sum
5	Container With Most Water	Container With Most Water
6	Longest Palindromic Substring	Longest Palindromic Substring
7	Add Two Numbers	Add Two Numbers
8	Generate Parentheses	Generate Parentheses
9	Merge Intervals	Merge Intervals
10	Basic Calculator	Basic Calculator
11	Basic Calculator II	Basic Calculator II
12	Regular Expression Matching	Regular Expression Matching
13	Trapping Rain Water	Trapping Rain Water
14	Daily Temperatures	Daily Temperatures
15	Merge k Sorted Lists	Merge k Sorted Lists
16	Reverse Nodes in k-Group	Reverse Nodes in k-Group
17	Valid Sudoku	Valid Sudoku
18	Sudoku Solver	Sudoku Solver
19	Count and Say	Count and say
20	Multiply Strings	Multiply Strings
21	Maximum Subarray	Maximum Subarray
22	Spiral Matrix	Spiral Matrix
23	Minimum Path Sum	Minmum Path Sum
24	Sort Colors	Sort Colors
25	Number of Islands	Number of Islands
26	Course Schedule	Course Schedule
27	Valid Anagram	Valid Anagram
28	Move Zeroes	Move Zeroes
29	Top K Frequent Elements	Top K Frequent Elements
30	Subarray Sum Equals K	Subarray Sum Equals K
31	Maximum Number of Balloons	here
32	Jump Game II	Jump Gmae II.
33	Largest Number	Largest Number

TikTok

(Back to top)

No.	Questions	Solution in PyCharm
1	Merge Intervals	Merge Intervals
2	Container With Most Water	Container With Most Water
3	Longest Substring Without Repeating Characters	Longest Substring Without Repeating Characters
4	Search in Rotated Sorted Array	Search in Rotated Sorted Array
5	Word Search	Word Search
6	Word Break	Word Break
7	Number of Islands	Number of Islands
8	Coin Change	Coin Change
9	Median of Two Sorted Arrays	Median of Two Sorted Arrays
10	Sliding Window Maximum	Sliding Window Maximum
11	Product of Array Except Self	Product of Array Except Self
12	Lowest Common Ancestor of a Binary Tree	Lowest Common Ancestor of a Binary Tree
13	Kth Largest Element in an Array	Kth Largest Element in an Array
14	Word Search II	Word Search II
15	Find Minimum in Rotated Sorted Array	Find Minimum in Rotated Sorted Array
16	Valid Palindrome	Valid Palindrome
17	Count Primes	Count Primes
18	House Robber	House Robber
19	Decode Ways	Decode Ways
20	Word Search	Word Search
21	Subsets	Subsets
22	Unique Paths	Unique Paths
23	Jump Game	Jump Game
24	Spiral Matrix	Spiral Matrix
25	Maximum Subarray	Maximum Subarray
26	N-Queens	N-Queens
27	Pow(x, n)	Pow(x, n)
28	Group Anagrams	Group Anagrams
29	Permutations	Permutations
30	Combination Sum	Combination Sum
31	Valid Parentheses	Valid Parentheses
32	Longest Valid Parentheses	Longest Valid Parentheses
33	Next Permutation	Next Permutation
34	Generate Parentheses	Generate Parentheses
35	3Sum Closest	3Sum Closest
36	3Sum	3Sum
37	Roman to Integer	Roman to Integer
38	Longest Palindromic Substring	Longest Palindromic Substring
39	Best Time to Buy and Sell Stock	Best Time to Buy and Sell Stock
40	Happy Number	Happy Number
41	Find Median from Data Stream	Find Median from Data Stream
42	Add Strings	Add Strings
43	Reverse Nodes in k-Group	Reverse Nodes in k-Group
44	Multiply Strings	Multiply Strings
45	Course Schedule	Course Schedule
46	Move Zeroes	Move Zeroes
47	Top K Frequent Elements	Top K Frequent Elements
48	Subarray Sum Equals K	Subarray Sum Equals K
49	Jump Game II	Jump Gmae II.
50	Excel Sheet Column Title	Excel Sheet Column Title
51	Longest Word in Dictionary	Longest Word in Dictionary
52	Walls And Gates	Walls And Gates

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Twitter

(Back to top)

No.	Questions	Solution in PyCharm
1	Two Sum	Two Sum
2	Sliding Window Maximum	Sliding Window Maximum
3	Maximal Square	Maximal Square
4	Word Search II	Word Search II
5	Implement Trie (Prefix Tree)	Implement Trie (Prefix Tree)
6	Word Break	Word Break
7	Clone Graph	Clone Graph
8	Longest Consecutive Sequence	Longest Consecutive Sequence
9	Pascal's Triangle	Pascal's Triangle
10	Count Primes	Count Primes
11	Word Search	Word Search
12	Subsets	Subsets
13	Insert Interval	Insert Interval
14	Merge Intervals	Merge Intervals
15	Group Anagrams	Group Anagrams
16	Trapping Rain Water	Trapping Rain Water
17	Valid Parentheses	Valid Parentheses
18	Letter Combinations of a Phone Number	Letter Combinations of a Phone Number
19	Add Two Numbers	Add Two Numbers
20	Lowest Common Ancestor of a Binary Search Tree	Lowest Common Ancestor of a Binary Search Tree
21	Regular Expression Matching	Regular Expression Matching
22	Wildcard Matching	Wildvard Matching
23	Happy Number	Happy Number
24	Alien Dictionary	Alien Dictionary
25	Find Median from Data Stream	Find Median from Data Stream
26	Multiply Strings	Multiply Strings
27	Top K Frequent Elements	Top K Frequent Elements

---

Uber

(Back to top)

No.	Questions	Solution in PyCharm
1	Two Sum	Two Sum
2	Merge Two Sorted Lists	Merge Two Sorted Lists
3	Merge k Sorted Lists	Merge k Sorted Lists
4	Contains Duplicate	Contains Duplicate
5	Valid Parentheses	Valid Parentheses
6	Climbing Stairs	Climbing Stairs
7	Container With Most Water	Container With Most Water
8	3Sum	3Sum
9	Longest Substring Without Repeating Characters	Longest Substring Without Repeating Characters
10	Longest Palindromic Substring	Longest Palindromic Substring
11	Rotate Image	Rotate Image
12	Search in Rotated Sorted Array	Search in Rotated Sorted Array
13	Word Search	Word Search
14	Number of Islands	Number of Islands
15	Maximum Subarray	Maximum Subarray
16	Product of Array Except Self	Product of Array Except Self
17	Median of Two Sorted Arrays	Median of Two Sorted Arrays
18	Palindrome Permutation	Palindrome Permutation
19	Shortest Word Distance	Shortest Word Distance
20	Search a 2D Matrix II	Search a 2D Matrix II
21	Sliding Window Maximum	Sliding Window Maximum
22	Lowest Common Ancestor of a Binary Tree	Lowest Common Ancestor of a Binary Tree
23	The Skyline Problem	The Skyline Problem
24	Kth Largest Element in an Array	Kth Largest Element in an Array
25	Word Search II	Word Search II
26	Implement Trie (Prefix Tree)	Implement Trie (Prefix Tree)
27	Best Time to Buy and Sell Stock IV	Best Time to Buy and Sell Stock IV
28	Binary Search Tree Iterator	Binary Search Tree Iterator
29	Two Sum II - Input array is sorted	Two Sum II - Input Array Is Sorted
30	Min Stack	Min Stack
31	Find Minimum in Rotated Sorted Array	Find Minimum in Rotated Sorted Array
32	Maximum Product Subarray	Maximum Product Subarray
33	Word Break	Word Break
34	Clone Graph	Clone Graph
35	Longest Consecutive Sequence	Longest Consecutive Sequence
36	Word Ladder	Word Ladder
37	Best Time to Buy and Sell Stock II	Best Time to Buy and Sell Stock II
38	Best Time to Buy and Sell Stock	Best Time to Buy and Sell Stock
39	Pascal's Triangle	Pascal's Triangle
40	Valid Palindrome	Valid Palindrome
41	Reverse Linked List	Reverse Linked List
42	Decode Ways	Decode Ways
43	Merge Sorted Array	Merge Sorted Array
44	Word Search	Word Search
45	Subsets	Subsets
46	Climbing Stairs	Climbing Stairs
47	Minimum Path Sum	Minmum Path Sum
48	Unique Paths	Unique Paths
49	Insert Interval	Insert Interval
50	Merge Intervals	Merge Intervals
51	Jump Game	Jump Game
52	Spiral Matrix	Spiral Matrix
53	N-Queens	N-Queens
54	Pow(x, n)	Pow(x, n)
55	Group Anagrams	Group Anagrams
56	Permutations	Permutations
57	Trapping Rain Water	Trapping Rain Water
58	Combination Sum	Combination Sum
59	Valid Sudoku	Valid Sudoku
60	Longest Valid Parentheses	Longest Valid Parentheses
61	Next Permutation	Next Permutation
62	Find the Index of the First Occurrence in a String	Find the Index of the First Occurrence in a String
63	Generate Parentheses	Generate Parentheses
64	Letter Combinations of a Phone Number	Letter Combinations of a Phone Number
65	3Sum Closest	3Sum Closest
66	Roman to Integer	Roman to Integer
67	String to Integer (atoi)	String to Integer (atoi)
68	Longest Palindromic Substring	Longest Palindromic Substring
69	Add Two Numbers	Add Two Numbers
70	Daily Temperatures	Daily Temperatures
71	Basic Calculator	Basic Calculator
72	Lowest Common Ancestor of a Binary Search Tree	Lowest Common Ancestor of a Binary Search Tree
73	Regular Expression Matching	Regular Expression Matching
74	Wildcard Matching	Wildvard Matching
75	Reverse Bits	Reverse bits.
76	Contains Duplicate II	Contains Duplicate II
77	Basic Calculator II	Basic Calculator II
78	Alien Dictionary	Alien Dictionary
79	Find Median from Data Stream	Find Median from Data Stream
80	Reverse Nodes in k-Group	Reverse Nodes in k-Group
81	Sudoku Solver	Sudoku Solver
82	Sort Colors	Sort Colors
83	Move Zeroes	Move Zeroes
84	Subarray Sum Equals K	Subarray Sum Equals K
85	Jump Game II	Jump Gmae II.
86	Excel Sheet Column Title	Excel Sheet Column Title
87	Reverse Words in a String	Reverse Words in a String
88	Strobogrammatic Number	Strobogrammatic Number
89	Search a 2D Matrix	Search a 2D Matrix
90	Largest Number	Largest Number
91	Invert Binary Tree	Invert Binary Tree
92	Guess Number Higher or Lower	Guess Number Higher or Lower
93	Walls And Gates	Walls And Gates
94	Symmetric Tree	Symmetric Tree

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Others

(Back to top)

No.	Questions	Solution in PyCharm
1	Mirror Reflection	Mirror Reflection

License

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