LeetCodeSwiftSolutions

Solutions for Leet Code problems with swift 4.2 .

Now is Binary Tree

ID (Hyperlink in this repo)	Finished Problems (Hyperlink in LeetCode/LeetCode-cn)	Difficulty	Tag
1	Two Sum	Easy	Array
17	Letter Combinations of a Phone Number	Medium	Backtracking
22	Generate Parentheses	Medium	Backtracking, DFS
39	Combination Sum	Medium	Backtracking
40	Combination Sum II	Medium	Backtracking
46	Permutations	Medium	Backtracking
47	Permutations II	Medium	Backtracking
offer-06	从尾到头打印链表	Easy	Stack
offer-09	用两个栈实现队列	Easy	Stack
offer-21	调整数组顺序使奇数位于偶数前面	Easy	Array
offer-22	链表中倒数第k个节点	Easy	Linked List
offer-30	包含min函数的栈	Easy	Stack
offer-31	栈的压入、弹出序列	Medium	Stack
offer-36	二叉搜索树与双向链表	Medium	Stack
offer-47	礼物的最大价值	Medium	DP
offer-50	第一个只出现一次的字符	Easy	Hash
53	Maximum Subarray	Easy	Array, DP
54	Spiral Matrix	Medium	Array
offer-59-2	队列的最大值	Medium	Stack
70	Climbing Stairs	Easy	Dynamic Programming
77	Combinations	Medium	Backtracking
78	Subsets	Medium	Backtracking
90	Subsets II	Medium	Backtracking
94	Binary Tree Inorder Traversal	Medium	Binary Tree
101	Symmetric Tree	Easy	Binary Tree
102	Binary Tree Level Order Traversal	Medium	Binary Tree
104	Maximum Depth of Binary Tree	Easy	Binary Tree
105	Construct Binary Tree from Preorder and Inorder Traversal	Medium	Binary Tree
106	Construct Binary Tree from Inorder and Postorder Traversal	Medium	Binary Tree
112	Path Sum	Easy	Binary Tree
116	Populating Next Right Pointers in Each Node	Medium	Binary Tree
117	Populating Next Right Pointers in Each Node II	Medium	Binary Tree
121	Best Time to Buy and Sell Stock	Easy	Array, DP
144	Binary Tree Preorder Traversal	Medium	Binary Tree
145	Binary Tree Postorder Traversal	Hard	Binary Tree
216	Combination Sum III	Medium	Backtracking
236	Lowest Common Ancestor of a Binary Tree	Medium	Binary Tree
301	Remove Invalid Parentheses	Hard	DFS, BFS
784	Letter Case Permutation	Medium	Backtracking