头铁坚持，转行打卡每日刷题

78.Subsets   #20200402
90.Subsets II   #20200402
46.Permutations  #20200402

47.Permutations II  #20200404
17. Letter Combinations of a Phone Number  #20200404







补充内容 (2020-4-5 06:05):
31. Next Permutation    #20200404
1053.Previous Permutation With One Swap    #20200404
39. Combination Sum    #20200404
40. Combination Sum II    #20200404
131. Palindrome Partitioning    #20200404

#042520 二叉树主题

中序遍历路径和前序类似，在不需要递归的循环解法中，都是先保存root，在遍历left之后可以立即弹出root； 而后序的做法需要利用peekNode先调用root先遍历右子树，再回到root（还需要判断此时是从左子树回来的还是右子树回来的）
145. Binary Tree Postorder Traversal
94. Binary Tree Inorder Traversal(Hard)

124. Binary Tree Maximum Path Sum(Hard)
       return singlepath和maxpath的tuple

ayaner 发表于 2020-4-6 12:37
93. Restore IP Addresses    #20200405  犯了一个低级错误但检查了半天没检查出来：(s[0] == '0'，而不是s ...

二分法系列

34. Find First and Last Position of Element in Sorted Array    #040620

35. Search Insert Position    #040620



补充内容 (2020-4-8 11:44):
33. Search in Rotated Sorted Array    #040720

补充内容 (2020-4-8 11:44):
81. Search in Rotated Sorted Array II    #040720

补充内容 (2020-4-8 11:44):
278. First Bad Version    #040720

补充内容 (2020-4-8 11:45):
162. Find Peak Element    #040720

补充内容 (2020-4-8 11:45):
74. Search a 2D Matrix    #040720

补充内容 (2020-4-8 11:46):
240. Search a 2D Matrix II    #040720

补充内容 (2020-4-11 12:24):
153. Find Minimum in Rotated Sorted Array    #041020

补充内容 (2020-4-11 12:25):
154. Find Minimum in Rotated Sorted Array II    #041020

#052620

Majority Number III
121. Best Time to Buy and Sell Stock
122. Best Time to Buy and Sell Stock II
123. Best Time to Buy and Sell Stock III
188. Best Time to Buy and Sell Stock IV  （这题太难理解了，用了dp看了答案还是一知半解，先这样回头再看）
Lintocde 1310. Product of Array Except Self

沙发，此帖必火，顶LZ

每日一题 发表于 2020-4-4 12:45
沙发，此帖必火，顶LZ

感谢支持！

93. Restore IP Addresses    #20200405  犯了一个低级错误但检查了半天没检查出来：(s[0] == '0'，而不是s[0] == 0)
132. Palindrome Partitioning II    #20200405 （用递归写的暴力解，之后学了动态规划再写最优解）

88. Merge Sorted Array    #041020

4. Median of Two Sorted Arrays    #041020


补充内容 (2020-4-12 12:29):
796. Rotate String    #041120

补充内容 (2020-4-12 12:29):
151. Reverse Words in a String    #041120

补充内容 (2020-4-12 12:31):
104. Maximum Depth of Binary Tree    #041120 （二叉树遍历相关）

补充内容 (2020-4-13 13:18):
98. Validate Binary Search Tree    #0412200  BST(binary search tree)

补充内容 (2020-4-13 13:19):
110. Balanced Binary Tree    #041220

补充内容 (2020-4-13 13:20):
100. Same Tree    #041220

补充内容 (2020-4-13 13:21):
102. Binary Tree Level Order Traversal    #041220

补充内容 (2020-4-22 08:56):
144. Binary Tree Preorder Traversal

#042720  二叉树宽度优先遍历

236. Lowest Common Ancestor of a Binary Tree
235. Lowest Common Ancestor of a Binary Search Tree
103. Binary Tree Zigzag Level Order Traversal
107. Binary Tree Level Order Traversal II

#042820

二叉树中序遍历，用全局变量
173. Binary Search Tree Iterator

13号到22号之间好像没打卡也没补啊。。