algorithm_camp

For leetcode.

String

NO.	Difficulty	Title	Answer
14	Easy	Longest Common Prefix	Longest Common Prefix
58	Easy	Length of Last Word	Length of Last Word
125	Easy	Valid Palindrome	Valid Palindrome
151	Medium	Reverse Words in a String	Reverse Words in a String
205	Easy	Isomorphic Strings	Isomorphic Strings
387	Easy	First Unique Character in a String	First Unique Character in a String
541	Easy	Reverse String II	Reverse String II
557	Easy	Reverse Words in a String III	Reverse Words in a String III
680	Easy	Valid Palindrome II	Valid Palindrome II

Array

NO.	Difficulty	Title	Answer
1	Easy	Two Sum	Two Sum
26	Easy	Remove Duplicates from Sorted Array	Remove Duplicates from Sorted Array
36	Medium	Valid Sudoku	Valid Sudoku
54	Medium	Spiral Matrix	Spiral Matrix
66	Easy	Plus One	Plus One
88	Easy	Merge Sorted Array	Merge Sorted Array
189	Medium	Rotate Array	Rotate Array
283	Easy	Move Zeroes	Move Zeroes
485	Easy	Max Consecutive Ones	Max Consecutive Ones
724	Easy	Find Pivot Index	Find Pivot Index
729	Medium	My Calendar I	My Calendar I
937	Easy	Reorder Data in Log Files	Reorder Data in Log Files
977	Easy	Squares of a Sorted Array	Squares of a Sorted Array
1089	Easy	Duplicate Zeros	Duplicate Zeros
1122	Easy	Relative Sort Array	Relative Sort Array
1295	Easy	Find Numbers with Even Number of Digits	Find Numbers with Even Number of Digits

LinkedList

NO.	Difficulty	Title	Answer
21	Easy	Merge Two Sorted Lists	Merge Two Sorted Lists
24	Medium	Swap Nodes in Pairs	Swap Nodes in Pairs
141	Easy	Linked List Cycle	Linked List Cycle
206	Easy	Reverse Linked List	Reverse Linked List
707	Medium	Design Linked List	Design Linked List

Two pointers

NO.	Difficulty	Title	Answer
167	Medium	Two Sum II - Input Array Is Sorted	Two Sum II - Input Array Is Sorted

Stack

NO.	Difficulty	Title	Answer
20	Easy	Valid Parentheses	Valid Parentheses
155	Easy	Min Stack	Min Stack
917	Easy	Reverse Only Letters	Reverse Only Letters

Queue

NO.	Difficulty	Title	Answer
239	Hard	Sliding Window Maximum	Sliding Window Maximum
622	Medium	Design Circular Queue	Design Circular Queue

Greedy

NO.	Difficulty	Title	Answer
621	Medium	Task Scheduler	Task Scheduler
860	Easy	Lemonade Change	Lemonade Change

Hash

NO.	Difficulty	Title	Answer
49	Easy	Group Anagrams	Group Anagrams
136	Easy	Single Number	Single Number
169	Easy	Majority Element	Majority Element
217	Easy	Contains Duplicate	Contains Duplicate
266	Easy	Palindrome Permutation	Palindrome Permutation
349	Easy	Intersection of Two Arrays	Intersection of Two Arrays
438	Medium	Find All Anagrams in a String	Find All Anagrams in a String
705	Easy	Design HashSet	Design HashSet
706	Easy	Design HashMap	Design HashMap
709	Easy	To Lower Case	To Lower Case
771	Easy	Jewels and Stones	Jewels and Stones

Sort

NO.	Difficulty	Title	Answer
242	Easy	Valid Anagram	Valid Anagram

BinaryTree

NO.	Difficulty	Title	Answer
94	Medium	Binary Tree Inorder Traversal	Binary Tree Inorder Traversal
102	Medium	Binary Tree Level Order Traversal	Binary Tree Level Order Traversal
144	Medium	Binary Tree Preorder Traversal	Binary Tree Preorder Traversal
145	Medium	Binary Tree Postorder Traversal	Binary Tree Postorder Traversal

N-ary tree

NO.	Difficulty	Title	Answer
589	Easy	N-ary Tree Preorder Traversal	N-ary Tree Postorder Traversal
590	Easy	N-ary Tree Postorder Traversal	N-ary Tree Postorder Traversal

BinarySearchTree

NO.	Difficulty	Title	Answer
98	Medium	Validate Binary Search Tree	Validate Binary Search Tree

BinarySearch

NO.	Difficulty	Title	Answer
33	Medium	Search in Rotated Sorted Array	Search in Rotated Sorted Array
50	Medium	Pow(x, n)	Pow(x, n)
69	Easy	Sqrt(x)	Sqrt(x)
374	Easy	Guess Number Higher or Lower	Guess Number Higher or Lower
704	Easy	Binary Search	Binary Search

Divide and Conquer

NO.	Difficulty	Title	Answer
912	Medium	Sort an Array	Sort an Array

Backtracking

NO.	Difficulty	Title	Answer
22	Medium	Generate Parentheses	Generate Parentheses
46	Medium	Permutations	Permutations
77	Medium	Combinations	Permutations
78	Medium	Subsets	Subsets

Recrusion

NO.	Difficulty	Title	Answer
344	Easy	Reverse String	Reverse String

DFS

NO.	Difficulty	Title	Answer
200	Medium	Number of Islands	Number of Islands
212	Hard	Word Search II	Word Search II

BFS

NO.	Difficulty	Title	Answer
127	Hard	Word Ladder	Word Ladder

DynamicProgramming

NO.	Difficulty	Title	Answer
62	Medium	Unique Paths	Unique Paths
63	Medium	Unique Paths II	Unique Paths II
64	Medium	Minimum Path Sum	Minimum Path Sum
70	Easy	Climbing Stairs	Climbing Stairs
91	Medium	Decode Ways	Decode Ways
120	Medium	Triangle	Triangle
121	Easy	Best Time to Buy and Sell Stock	Best Time to Buy and Sell Stock
122	Easy	Best Time to Buy and Sell Stock II	Best Time to Buy and Sell Stock II
198	Medium	House Robber	House Robber
221	Medium	Maximal Square	Maximal Square
322	Medium	Coin Change	Coin Change
647	Medium	Palindromic Substrings	Palindromic Substrings
746	Easy	Min Cost Climbing Stairs	Min Cost Climbing Stairs
1143	Medium	Longest Common Subsequence	Longest Common Subsequence

Trier

NO.	Difficulty	Title	Answer
208	Medium	Implement Trie (Prefix Tree)	Implement Trie (Prefix Tree)

Heap

NO.	Difficulty	Title	Answer
347	Medium	Top K Frequent Elements	Top K Frequent Elements

Graph

NO.	Difficulty	Title	Answer
210	Medium	Course Schedule II	Course Schedule II

Bit Operation

NO.	Difficulty	Title	Answer
190	Easy	Reverse Bits	Reverse Bits
191	Easy	Number of 1 Bits	Number of 1 Bits
231	Easy	Power of Two	Power of Two
338	Easy	Counting Bits	Counting Bits

LRU

NO.	Difficulty	Title	Answer
146	Medium	LRU Cache	LRU Cache

Union Find

NO.	Difficulty	Title	Answer
547	Medium	Number of Provinces	Number of Provinces