LeetCode 解题攻略——Kotlin

引言

这篇文章的输出并不是作者计划好的，它来源于作者的一个习惯。这个习惯就是每周都会解决一道LeetCode的题目，从毕业至今一直保持着。最近突然发现每周的一道题和一篇解题思路的文章已经累积到60+，于是水到渠成地决定写下这篇汇总文章，既是对过去的总结，也希望能对他人有一些启发。

汇总

已经完成的LeetCode题目按问题难度汇总到下方的表格，分为Easy/Medium/Hard三部分，Title列点击题目可以跳转到该题答案和解题思路。

Easy

#	Title
717	1-bit and 2-bit Characters
804	Unique Morse Code Words
929	Unique Email Addresses
653	Two Sum IV - Input is a BST
709	To Lower Case
404	Sum of Left Leaves
905	Sort Array By Parity
922	Sort Array By Parity II
700	Search in a Binary Search Tree
938	Range Sum of BST
883	Projection Area of 3D Shapes
762	Prime Number of Set Bits in Binary Representation
852	Peak Index in a Mountain Array
876	Middle of the Linked List
771	Jewels and Stones
897	Increasing Order Search Tree
832	Flipping an Image
744	Find Smallest Letter Greater Than Target
760	Find Anagram Mappings
448	Find All Numbers Disappeared in an Array
942	DI String Match
944	Delete Columns to Make Sorted
696	Count Binary Substrings
538	Convert BST to Greater Tree
606	Construct String from Binary Tree
961	N-Repeated Element in Size 2N Array
977	Squares of a Sorted Array
965	Univalued Binary Tree
509	Fibonacci Number
985	Sum of Even Numbers After Queries
933	Number of Recent Calls
821	Shortest Distance to a Character
872	Leaf-Similar Trees
908	Smallest Range I
1002	Find Common Characters
836	Rectangle Overlap
783	Minimum Distance Between BST Nodes
303	Range Sum Query - Immutable
530	Minimum Absolute Difference in BST
645	Set Mismatch
1221	Split a String in Balanced Strings
1252	Cells with Odd Values in a Matrix
189	Rotate Array
896	Monotonic Array
1013	Partition Array Into Three Parts With Equal Sum
172	Factorial Trailing Zeroes
237	Delete Node in a Linked List
1185	Day of the Week
917	Reverse Only Letters
811	Subdomain Visit Count
1184	Distance Between Bus Stops
1323	Maximum 69 Number
1572	Matrix Diagonal Sum
1704	Determine if String Halves Are Alike
1304	Find N Unique Integers Sum up to Zero
1021	Remove Outermost Parentheses
1266	Minimum Time Visiting All Points
1266	Truncate Sentence
1732	Find the Highest Altitude
1854	Maximum Population Year
1370	Increasing Decreasing String
1528	Shuffle String
1470	Shuffle the Array
1480	Running Sum of 1d Array
28	Implement strStr()
35	Search Insert Position
88	Merge Sorted Array
9	Palindrome Number
94	Binary Tree Inorder Traversal
543	Diameter of Binary Tree
14	Longest Common Prefix
1859	Sorting the Sentence

Medium

#	Title
861	Score After Flipping Matrix
950	Reveal Cards In Increasing Order
763	Partition Labels
921	Minimum Add to Make Parentheses Valid
807	Max Increase to Keep City Skyline
701	Insert into a Binary Search Tree
515	Find Largest Value in Each Tree Row
890	Find and Replace Pattern
814	Binary Tree Pruning
797	All Paths From Source to Target
894	All Possible Full Binary Trees
399	Evaluate Division
328	Odd Even Linked List
16	3Sum Closest
147	Insertion Sort List
802	Find Eventual Safe States
59	Spiral Matrix II
162	Find Peak Element
56	Merge Intervals
831	Masking Personal Information
725	Split Linked List in Parts
855	Exam Room
791	Custom Sort String
1038	Binary Search Tree to Greater Sum Tree
380	Insert Delete GetRandom O(1)
516	Longest Palindromic Subsequence
1008	Construct Binary Search Tree from Preorder Traversal
93	Restore IP Addresses
912	Sort an Array
63	Unique Paths II
910	Smallest Range II
109	Convert Sorted List to Binary Search Tree
64	Minimum Path Sum
1282	Group the People Given the Group Size They Belong To
43	Multiply Strings
990	Satisfiability of Equality Equations
655	Print Binary Tree
260	Single Number III
1238	Circular Permutation in Binary Representation
667	Beautiful Arrangement II
1006	Clumsy Factorial
113	Path Sum II
769	Max Chunks To Make Sorted
962	Maximum Width Ramp
462	Minimum Moves to Equal Array Elements II
98	Validate Binary Search Tree
1395	Count Number of Teams
1315	Sum of Nodes with Even-Valued Grandparent
1637	Widest Vertical Area Between Two Points Containing No Points
1302	Deepest Leaves Sum
1329	Sort the Matrix Diagonally
1325	Delete Leaves With a Given Value
1382	Balance a Binary Search Tree
1476	Subrectangle Queries
1669	Merge In Between Linked Lists
1409	Queries on a Permutation With Key
1630	Arithmetic Subarrays
2	Add Two Numbers
1605	Find Valid Matrix Given Row and Column Sums
1551	Minimum Operations to Make Array Equal
1641	Count Sorted Vowel Strings
1079	Letter Tile Possibilities
1305	All Elements in Two Binary Search Trees
1877	Minimize Maximum Pair Sum in Array
5	Longest Palindromic Substring
3	Longest Substring Without Repeating Characters
15	3Sum
90	Subsets II
62	Unique Paths
12	Integer to Roman
39	Combination Sum
11	Container With Most Water
33	Search in Rotated Sorted Array
107	Binary Tree Level Order Traversal II
129	Sum Root to Leaf Numbers
46	Permutations
102	Binary Tree Level Order Traversal
61	Rotate List
179	Largest Number
34	Find First and Last Position of Element in Sorted Array

Hard

#	Title
57	Insert Interval
446	Arithmetic Slices II - Subsequence
410	Split Array Largest Sum
51	N-Queens
928	Minimize Malware Spread II
943	Find the Shortest Superstring
312	Burst Balloons
330	Patching Array
1206	Design Skiplist
32	Longest Valid Parentheses

总结

不积跬步，无以至千里；不积小流，无以成江海。作者毕业至今保持着每周一道LeetCode的习惯，不知不觉中已经完成了100+的题目。通过梳理题目，总结解题思路，解题的效率也越来越高，效果还是很明显的。很推荐大家通过做LeetCode题目的方式保持思维的活跃，从枯燥的业务中适当释放一下，既能提高逻辑思维能力，也能提高对算法和数据结构的理解。