leetcode-solutions

This is a repository with my solutions to problems from www.leetcode.com.

Problems

#	Title	Solution	Difficulty
1	Decode XORed Array	Solution	EASY
2	Count Operations to Obtain Zero	Solution	EASY
3	Best Time to Buy and Sell Stock	Solution	EASY
4	Print in Order	Solution	EASY
5	Print in Order	SolutionV3	EASY
6	Print in Order	SolutionV2	EASY
7	Palindrome Number	Solution	EASY
8	Sum of Two Integers	Solution	EASY
9	Number of Even and Odd Bits	Solution	EASY
10	Pascals Triangle	Solution	EASY
11	Number of Steps to Reduce a Number to Zero	Solution	EASY
12	Buy Two Chocolates	Solution	EASY
13	Two Sum	Solution	EASY
14	Binary Tree Postorder Traversal	Solution	EASY
15	Squares of a Sorted Array	Solution	EASY
16	Remove Letter To Equalize Frequency	Solution	EASY
17	Plus One	Solution	EASY
18	Counter	Solution.js	EASY
19	Isomorphic Strings	Solution	EASY
20	Search Insert Position	Solution	EASY
21	Add Digits	Solution	EASY
22	Sqrt(x)	Solution	EASY
23	Length of Last Word	Solution	EASY
24	Island Perimeter	Solution	EASY
25	Island Perimeter	SolutionV2	EASY
26	Add Binary	Solution	EASY
27	Binary Tree Inorder Traversal	Solution	EASY
28	Implement Queue using Stacks	Solution	EASY
29	Nim Game	Solution	EASY
30	Find the Pivot Integer	Solution	EASY
31	Minimum Bit Flips to Convert Number	Solution	EASY
32	Missing Number	Solution	EASY
33	Missing Number	SolutionV2	EASY
34	Valid Parentheses	Solution	EASY
35	Backspace String Compare	Solution	EASY
36	Backspace String Compare	SolutionV2	EASY
37	Remove Element	Solution	EASY
38	Furthest Point From Origin	Solution	EASY
39	Add Strings	Solution	EASY
40	Running Sum of 1d Array	Solution	EASY
41	Fizz Buzz	Solution	EASY
42	Valid Palindrome II	Solution	EASY
43	Contains Duplicate II	Solution	EASY
44	Contains Duplicate II	SolutionV2	EASY
45	Implement strStr()	Solution	EASY
46	Implement strStr()	SolutionV2	EASY
47	Average Value of Even Numbers That Are Divisible by Three	Solution	EASY
48	Valid Anagram	Solution	EASY
49	Remove Duplicates from Sorted Array	Solution	EASY
50	Reverse Prefix of Word	Solution	EASY
51	Merge Two Sorted Lists	Solution	EASY
52	Maximum Average Subarray I	Solution	EASY
53	Maximum Average Subarray I	SolutionV2	EASY
54	Number Complement	Solution	EASY
55	Merge Sorted Array	Solution	EASY
56	Crawler Log Folder	Solution	EASY
57	Majority Element	Solution	EASY
58	Majority Element	SolutionV2	EASY
59	Merge Strings Alternately	Solution	EASY
60	A Number After a Double Reversal	Solution	EASY
61	Reverse Words in a String III	Solution	EASY
62	Reverse Words in a String III	SolutionV2	EASY
63	Sort Integers by The Number of 1 Bits	Solution	EASY
64	Excel Sheet Column Title	Solution	EASY
65	Design HashMap	Solution	EASY
66	Sum of Squares of Special Elements	Solution	EASY
67	Maximum Depth of Binary Tree	Solution	EASY
68	Maximum Length Substring With Two Occurrences	Solution	EASY
69	Counting Bits	Solution	EASY
70	Counting Bits	SolutionV2	EASY
71	Find First Palindromic String in the Array	Solution	EASY
72	Reverse String	Solution	EASY
73	Excel Sheet Column Number	Solution	EASY
74	Valid Palindrome	Solution	EASY
75	Reverse String II	Solution	EASY
76	Reverse String II	SolutionV2	EASY
77	First Letter to Appear Twice	Solution	EASY
78	Linked List Cycle	Solution	EASY
79	UNKNOWN	Solution	EASY
80	Divide a String Into Groups of Size k	Solution	EASY
81	Power of Four	Solution	EASY
82	Find the Difference	Solution	EASY
83	Find Smallest Letter Greater Than Target	Solution	EASY
84	Find Smallest Letter Greater Than Target	SolutionV2	EASY
85	Path Sum	Solution	EASY
86	Word Pattern	Solution	EASY
87	Hamming Distance	Solution	EASY
88	Hamming Distance	SolutionV3	EASY
89	Hamming Distance	SolutionV2	EASY
90	Construct the Rectangle	Solution	EASY
91	Reverse Linked List	Solution	EASY
92	Positions of Large Groups	Solution	EASY
93	Positions of Large Groups	SolutionV2	EASY
94	Number of Segments in a String	Solution	EASY
95	Complement of Base 10 Integer	Solution	EASY
96	Reformat Phone Number	Solution	EASY
97	Number of Unequal Triplets in Array	Solution	EASY
98	Check if Numbers Are Ascending in a Sentence	Solution	EASY
99	Power of Two	Solution	EASY
100	Power of Two	SolutionV2	EASY
101	Check if Number Has Equal Digit Count and Digit Value	Solution	EASY
102	Most Frequent Even Element	Solution	EASY
103	Remove Duplicates from Sorted List	Solution	EASY
104	Implement Stack using Queues	Solution	EASY
105	First Bad Version	Solution	EASY
106	Counter II	Solution.js	EASY
107	Baseball Game	Solution	EASY
108	Roman to Integer	Solution	EASY
109	Convert the Temperature	Solution	EASY
110	Longest Common Prefix	Solution	EASY
111	Move Zeroes	Solution	EASY
112	Symmetric Tree	Solution	EASY
113	Min Stack	Solution	EASY
114	Min Stack	SolutionV2	EASY
115	Fibonacci Number	Solution	EASY
116	Binary Search	Solution	EASY
117	Rearrange Spaces Between Words	Solution	EASY
118	Reverse Bits	Solution	EASY
119	Same Tree	Solution	EASY
120	Range Sum Query - Immutable	Solution	EASY
121	Single Number	Solution	EASY
122	Single Number	SolutionV2	EASY
123	Count Good Triplets	Solution	EASY
124	Check if All As Appears Before All Bs	Solution	EASY
125	Number of 1 Bits	Solution	EASY
126	Design HashSet	Solution	EASY
127	Is Subsequence	Solution	EASY
128	Text Justification	Solution	HARD
129	Design Skiplist	Solution	HARD
130	Valid Number	Solution	HARD
131	LFU Cache	Solution	HARD
132	Design a Text Editor	Solution	HARD
133	Reverse Integer	Solution	MEDIUM
134	UNKNOWN	Solution	MEDIUM
135	Validate Stack Sequences	Solution	MEDIUM
136	Zigzag Conversion	Solution	MEDIUM
137	Flatten Nested List Iterator	Solution	MEDIUM
138	Binary Search Tree Iterator	Solution	MEDIUM
139	String to Integer (atoi)	Solution	MEDIUM
140	Print FooBar Alternately	Solution	MEDIUM
141	Rotate List	Solution	MEDIUM
142	Spiral Matrix II	Solution	MEDIUM
143	Spiral Matrix II	SolutionV2	MEDIUM
144	UNKNOWN	Solution	MEDIUM
145	Single Number III	Solution	MEDIUM
146	Score of Parentheses	Solution	MEDIUM
147	Container With Most Water	Solution	MEDIUM
148	Max Number of K-Sum Pairs	Solution	MEDIUM
149	Minimum Remove to Make Valid Parentheses	Solution	MEDIUM
150	Jump Game II	Solution	MEDIUM
151	K Radius Subarray Averages	Solution	MEDIUM
152	Search a 2D Matrix	Solution	MEDIUM
153	Search a 2D Matrix	SolutionV2	MEDIUM
154	H-Index	Solution	MEDIUM
155	Find the Duplicate Number	Solution	MEDIUM
156	Majority Element II	Solution	MEDIUM
157	Encode and Decode TinyURL	Solution	MEDIUM
158	Maximum Depth of N-ary Tree	Solution	MEDIUM
159	Evaluate Reverse Polish Notation	Solution	MEDIUM
160	Building H2O	Solution	MEDIUM
161	Longest Substring Without Repeating Characters	Solution	MEDIUM
162	Longest Substring Without Repeating Characters	SolutionV2	MEDIUM
163	Flatten Binary Tree to Linked List	Solution	MEDIUM
164	Add Two Numbers	Solution	MEDIUM
165	LRU Cache	Solution	MEDIUM
166	Print Zero Even Odd	Solution	MEDIUM
167	Unique Paths	Solution	MEDIUM
168	Spiral Matrix	SolutionV2	MEDIUM
169	Append Characters to String to Make Subsequence	Solution	MEDIUM
170	Number of Islands	Solution	MEDIUM
171	Jump Game	Solution	MEDIUM
172	Unique Paths II	Solution	MEDIUM
173	Minimum Path Sum	Solution	MEDIUM
174	Map Sum Pairs	Solution	MEDIUM
175	Rotate Image	Solution	MEDIUM
176	Swap Nodes in Pairs	Solution	MEDIUM
177	Integer to Roman	Solution	MEDIUM
178	Simplify Path	Solution	MEDIUM
179	Remove Duplicates from Sorted List II	Solution	MEDIUM
180	Find The Original Array of Prefix Xor	Solution	MEDIUM
181	Peeking Iterator	Solution	MEDIUM
182	Peeking Iterator	SolutionV2	MEDIUM
183	Number of Matching Subsequences	Solution	MEDIUM
184	UTF-8 Validation	Solution	MEDIUM
185	Jump Game III	Solution	MEDIUM
186	Fizz Buzz Multithreaded	Solution	MEDIUM
187	Range Sum Query 2D - Immutable	Solution	MEDIUM
188	House Robber	Solution	MEDIUM
189	House Robber	SolutionV2	MEDIUM