LeetCode

(Notes: "🔒" means you need to buy subscription from Leetcode)

Directory

• Array
• Backtracking
• Bit Manipulation
• C
• Design
• Dynamic Programming
• Graph
• Linkedlist
• Math
• Random
• SqlBash
• Stack Priority Queue
• String
• Tree

Array

No	Title	Solution	Difficulty
4	Median of Two Sorted Arrays	Rust	Hard
11	Container With Most Water	Rust	Medium
21	Merge Two Sorted Lists	Rust	Easy
27	Remove Element	Rust	Easy
33	Search in Rotated Sorted Array	Rust	Hard
34	Search for a Range	Rust	Medium
35	Search Insert Position	Rust	Medium
42	Trapping Rain Water	Rust	Hard
45	Jump Game II	Rust	Hard
53	Maximum Subarray	Rust	Medium
75	Sort Colors	Rust	Medium
81	Search in Rotated Sorted Array II	Rust	Medium
88	Merge Sorted Array	Rust	Easy
121	Best Time to Buy and Sell Stock	Rust	Medium
122	Best Time to Buy and Sell Stock II	Rust	Medium
123	Best Time to Buy and Sell Stock III	Rust	Hard
135	Candy	Rust	Hard
152	Maximum Product Subarray	Rust	Medium
153	Find Minimum in Rotated Sorted Array	Rust	Medium
154	Find Minimum in Rotated Sorted Array II	Rust	Hard
162	Find Peak Element	Rust	Medium
163	Missing Ranges	Rust	Medium
164	Maximum Gap	Rust	Hard
188	Best Time to Buy and Sell Stock IV	Rust	Hard
209	Minimum Size Subarray Sum	Rust	Medium
228	Summary Ranges	Rust	Easy
229	Majority Element II	Rust	Medium
238	Product of Array Except Self	Rust	Medium
239	Sliding Window Maximum	Rust	Hard
243	Shortest Word Distance	Rust	Easy
252	Meeting Rooms	Rust	Easy
253	Meeting Rooms II	Rust	Medium
280	Wiggle Sort	Rust	Medium
283	Move Zeroes	Rust	Easy
287	Find the Duplicate Number	Rust	Hard
289	Game of Life	Rust	Medium
295	Find Median from Data Stream	Rust	Hard
300	Longest Increasing Subsequence	Rust	Medium
309	Best Time to Buy and Sell Stock with Cooldown	Rust	Medium
321	Create Maximum Number	Rust	Hard
324	Wiggle Sort II	Rust	Medium
325	Maximum Size Subarray Sum Equals k	Rust	Medium
330	Patching Array	Rust	Medium
334	Increasing Triplet Subsequence	Rust	Medium
349	Intersection of Two Arrays	Rust	Easy
350	Intersection of Two Arrays II	Rust	Easy
352	Data Stream as Disjoint Intervals	Rust	Hard
354	Russian Doll Envelopes	Rust	Hard
376	Wiggle Subsequence	Rust	Medium
560	Subarray Sum Equals K	Rust	Medium
575	Distribute Candies	Rust	Easy
581	Shortest Unsorted Continuous Subarray	Rust	Easy
665	Non-decreasing Array	Rust	Medium
674	Longest Continuous Increasing Subsequence	Rust	Easy
704	Binary Search	Rust	Easy
724	Find Pivot Index	Rust	Easy
821	Shortest Distance to a Character	Rust	Easy
896	Monotonic Array	Rust	Easy
904	Fruit Into Baskets	Rust	Medium
905	Sort Array By Parity	Rust	Easy
931	Minimum Falling Path Sum	Rust	Medium
939	Minimum Area Rectangle	Rust	Medium
941	Valid Mountain Array	Rust	Easy
969	Pancake Sorting	Rust	Medium
977	Squares of a Sorted Array	Rust	Easy
986	Interval List Intersections	Rust	Medium
989	Add to Array-Form of Integer	Rust	Easy
1053	Previous Permutation With One Swap	Rust	Medium
1266	Minimum Time Visiting All Points	Rust	Easy
1281	Subtract the Product and Sum of Digits of an Integer	Rust	Easy
1287	Element Appearing More Than 25% In Sorted Array	Rust	Easy
1299	Replace Elements with Greatest Element on Right Side	Rust	Easy
1314	Matrix Block Sum	Rust	Medium
1375	Bulb Switcher III	Rust	Medium

Backtracking

No	Title	Solution	Difficulty
17	Letter Combinations of a Phone Number	Rust	Medium
31	Next Permutation	Rust	Medium
39	Combination Sum	Rust	Medium
40	Combination Sum II	Rust	Medium
46	Permutations	Rust	Medium
47	Permutations II	Rust	Hard
60	Permutation Sequence	Rust	Medium
77	Combinations	Rust	Medium
78	Subsets	Rust	Medium
90	Subsets II	Rust	Medium
93	Restore IP Addresses	Rust	Medium
140	Word Break II	Rust	Hard
216	Combination Sum III	Rust	Medium
254	Factor Combinations	Rust	Medium
282	Expression Add Operators	Rust	Hard
291	Word Pattern II	Rust	Hard
320	Generalized Abbreviation	Rust	Medium
351	Android Unlock Patterns	Rust	Medium
377	Combination Sum IV	Rust	Medium
784	Letter Case Permutation	Rust	Medium
1219	Path with Maximum Gold	Rust	Medium

Bit Manipulation

No	Title	Solution	Difficulty
89	Gray Code	Rust	Medium
136	Single Number	Rust	Medium
137	Single Number II	Rust	Medium
191	Number of 1 Bits	Rust	Easy
201	Bitwise AND of Numbers Range	Rust	Medium
260	Single Number III	Rust	Medium
268	Missing Number	Rust	Medium
318	Maximum Product of Word Lengths	Rust	Medium
338	Counting Bits	Rust	Medium
371	Sum of Two Integers	Rust	Easy
389	Find the Difference	Rust	Easy
393	UTF-8 Validation	Rust	Medium

C

No	Title	Solution	Difficulty
116	Populating Next Right Pointers in Each Node	C	Medium
117	Populating Next Right Pointers in Each Node II	C	Hard
133	Clone Graph	C	Medium
138	Copy List with Random Pointer	C	Hard
141	Linked List Cycle	C	Medium
142	Linked List Cycle II	C	Medium
157	Read N Characters Given Read4	C	Easy
158	Read N Characters Given Read4 II - Call multiple times	C	Hard
160	Intersection of Two Linked Lists	C	Easy
190	Reverse Bits	C	Easy
235	Lowest Common Ancestor of a Binary Search Tree	C	Easy
236	Lowest Common Ancestor of a Binary Tree	C	Medium
237	Delete Node in a Linked List	C	Easy
284	Peeking Iterator	C	Medium
285	Inorder Successor in BST	C	Medium
297	Serialize and Deserialize Binary Tree	C	Medium

Design

No	Title	Solution	Difficulty
146	LRU Cache	Rust	Hard
170	Two Sum III - Data structure design	Rust	Easy
170	Flatten 2D Vector	Rust	Medium
281	Zigzag Iterator	Rust	Medium
288	Unique Word Abbreviation	Rust	Medium
303	Range Sum Query - Immutable	Rust	Easy
304	Range Sum Query 2D - Immutable	Rust	Medium
307	Range Sum Query - Mutable	Rust	Medium
308	Range Sum Query 2D - Mutable	Rust	Hard
346	Moving Average from Data Stream	Rust	Easy
348	Design Tic-Tac-Toe	Rust	Medium
353	Design Snake Game	Rust	Medium
355	Design Twitter	Rust	Medium
359	Logger Rate Limiter	Rust	Easy
362	Design Hit Counter	Rust	Medium
379	Design Phone Directory	Rust	Medium
731	My Calendar II	Rust	Medium
1032	Stream of Characters	Rust	Hard
1206	Design Skiplist	Rust	Hard
1352	Product of the Last K Numbers	Rust	Medium
1429	First Unique Number	Rust	Medium
1570	Dot Product of Two Sparse Vectors	Rust	Medium

Dynamic Programming

No	Title	Solution	Difficulty
10	Regular Expression Matching	Rust	Hard
44	Wildcard Matching	Rust	Hard
62	Unique Paths	Rust	Medium
63	Unique Paths II	Rust	Medium
70	Climbing Stairs	Rust	Easy
72	Edit Distance	Rust	Hard
85	Maximal Rectangle	Rust	Hard
91	Decode Ways	Rust	Medium
97	Interleaving String	Rust	Hard
120	Triangle	Rust	Medium
128	Longest Consecutive Sequence	Rust	Hard
139	Word Break	Rust	Medium
174	Dungeon Game	Rust	Hard
198	House Robber	Rust	Easy
213	House Robber II	Rust	Medium
221	Maximal Square	Rust	Medium
256	Paint House	Rust	Medium
265	Paint House II	Rust	Hard
276	Paint Fence	Rust	Easy
279	Perfect Squares	Rust	Medium
312	Burst Balloons	Rust	Hard
322	Coin Change	Rust	Medium
363	Max Sum of Rectangle No Larger Than K	Rust	Hard
375	Guess Number Higher or Lower II	Rust	Medium
413	Arithmetic Slices	Rust	Medium
1000	Minimum Cost to Merge Stones	Rust	Hard
1066	Campus Bikes II	Rust	Medium
1155	Number of Dice Rolls With Target Sum	Rust	Medium
1196	How Many Apples Can You Put into the Basket	Rust	Easy
1335	Minimum Difficulty of a Job Schedule	Rust	Hard
1504	Count Submatrices With All Ones	Rust	Medium

Graph

No	Title	Solution	Difficulty
51	N-Queens	Rust	Hard
52	N-Queens II	Rust	Hard
126	Word Ladder II	Rust	Hard
127	Word Ladder	Rust	Medium
130	Surrounded Regions	Rust	Medium
149	Max Points on a Line	Rust	Hard
200	Number of Islands	Rust	Medium
207	Course Schedule	Rust	Medium
210	Course Schedule II	Rust	Medium
223	Rectangle Area	Rust	Easy
261	Graph Valid Tree	Rust	Medium
269	Alien Dictionary	Rust	Hard
286	Walls and Gates	Rust	Medium
305	Number of Islands II	Rust	Hard
310	Minimum Height Trees	Rust	Medium
323	Number of Connected Components in an Undirected Graph	Rust	Medium
335	Self Crossing	Rust	Hard
339	Nested List Weight Sum	Rust	Easy
356	Line Reflection	Rust	Medium
364	Nested List Weight Sum II	Rust	Medium
391	Perfect Rectangle	Rust	Hard
399	Evaluate Division	Rust	Medium
444	Sequence Reconstruction	Rust	Medium
463	Island Perimeter	Rust	Easy
675	Cut Off Trees for Golf Event	Rust	Hard
695	Max Area of Island	Rust	Medium
766	Toeplitz Matrix	Rust	Easy
787	Cheapest Flights Within K Stops	Rust	Medium
841	Keys and Rooms	Rust	Medium
1254	Number of Closed Islands	Rust	Medium

Linkedlist

No	Title	Solution	Difficulty
2	Add Two Numbers	Rust	Medium
19	Remove Nth Node From End of List	Rust	Easy
21	Merge Two Sorted Lists	Rust	Easy
23	Merge k Sorted Lists	Rust	Hard
24	Swap Nodes in Pairs	Rust	Medium
25	Reverse Nodes in k-Group	Rust	Hard
61	Rotate List	Rust	Medium
82	Remove Duplicates from Sorted List II	Rust	Medium
83	Remove Duplicates from Sorted List	Rust	Easy
86	Partition List	Rust	Medium
92	Reverse Linked List II	Rust	Medium
143	Reorder List	Rust	Medium
147	Insertion Sort List	Rust	Medium
148	Sort List	Rust	Medium
203	Remove Linked List Elements	Rust	Easy
206	Reverse Linked List	Rust	Easy
234	Palindrome Linked List	Rust	Easy
328	Odd Even Linked List	Rust	Medium
369	Plus One Linked List	Rust	Medium
876	Middle of the Linked List	Rust	Easy

Math

No	Title	Solution	Difficulty
1	Two Sum	Rust	Easy
7	Reverse Integer	Rust	Easy
8	String to Integer (atoi)	Rust	Easy
15	3Sum	Rust	Medium
16	3Sum Closest	Rust	Medium
18	4Sum	Rust	Medium
29	Divide Two Integers	Rust	Medium
36	Valid Sudoku	Rust	Easy
37	Sudoku Solver	Rust	Hard
43	Multiply Strings	Rust	Medium
48	Rotate Image	Rust	Medium
50	"Pow(x, n)"	Rust	Medium
54	Spiral Matrix	Rust	Medium
59	Spiral Matrix II	Rust	Medium
66	Plus One	Rust	Easy
67	Add Binary	Rust	Easy
69	Sqrt(x)	Rust	Medium
73	Set Matrix Zeroes	Rust	Medium
74	Search a 2D Matrix	Rust	Medium
79	Word Search	Rust	Medium
165	Compare Version Numbers	Rust	Easy
166	Fraction to Recurring Decimal	Rust	Medium
167	Two Sum II - Input array is sorted	Rust	Medium
172	Factorial Trailing Zeroes	Rust	Easy
202	Happy Number	Rust	Easy
204	Count Primes	Rust	Easy
231	Power of Two	Rust	Easy
233	Number of Digit One	Rust	Medium
240	Search a 2D Matrix II	Rust	Medium
258	Add Digits	Rust	Easy
259	3Sum Smaller	Rust	Medium
292	Nim Game	Rust	Easy
296	Best Meeting Point	Rust	Hard
302	Smallest Rectangle Enclosing Black Pixels	Rust	Hard
306	Additive Number	Rust	Medium
311	Sparse Matrix Multiplication	Rust	Medium
317	Shortest Distance from All Buildings	Rust	Hard
319	Bulb Switcher	Rust	Medium
326	Power of Three	Rust	Easy
329	Longest Increasing Path in a Matrix	Rust	Medium
342	Power of Four	Rust	Easy
343	Integer Break	Rust	Medium
357	Count Numbers with Unique Digits	Rust	Medium
360	Sort Transformed Array	Rust	Medium
361	Bomb Enemy	Rust	Medium
365	Water and Jug Problem	Rust	Medium
367	Valid Perfect Square	Rust	Easy
368	Largest Divisible Subset	Rust	Medium
370	Range Addition	Rust	Medium
372	Super Pow	Rust	Medium
378	Kth Smallest Element in a Sorted Matrix	Rust	Medium
386	Lexicographical Numbers	Rust	Medium
390	Elimination Game	Rust	Medium
396	Rotate Function	Rust	Easy
397	Integer Replacement	Rust	Medium
400	Nth Digit	Rust	Medium
885	Spiral Matrix III	Rust	Medium
1131	Maximum of Absolute Value Expression	Rust	Medium
1137	N-th Tribonacci Number	Rust	Easy
1439	Find the Kth Smallest Sum of a Matrix With Sorted Rows	Rust	Hard
1518	Water Bottles	Rust	Easy

Random

No	Title	Solution	Difficulty
380	Insert Delete GetRandom O(1)	Rust	Hard
381	Insert Delete GetRandom O(1) - Duplicates allowed	Rust	Hard
382	Linked List Random Node	Rust	Medium
384	Shuffle an Array	Rust	Medium
398	Random Pick Index	Rust	Medium

SqlBash

No	Title	Solution	Difficulty
175	Combine Two Tables	SQL	Easy
176	Second Highest Salary	SQL	Easy
177	Nth Highest Salary	SQL	Medium
178	Rank Scores	SQL	Medium
180	Consecutive Numbers	SQL	Medium
181	Employees Earning More Than Their Managers	SQL	Easy
182	Duplicate Emails	SQL	Easy
183	Customers Who Never Order	SQL	Easy
184	Department Highest Salary	SQL	Medium
185	Department Top Three Salaries	SQL	Hard
192	Word Frequency	SHELL	Medium
193	Valid Phone Numbers	SHELL	Easy
194	Transpose File	SHELL	Medium
195	Tenth Line	SHELL	Easy
196	Delete Duplicate Emails	SQL	Easy
197	Rising Temperature	SQL	Easy
262	Trips and Users	SQL	Hard
595	Big Countries	SQL	Easy
627	Swap Salary	SQL	Easy
620	Not Boring Movies	SQL	Easy
596	Classes More Than 5 Students	SQL	Easy
626	Exchange Seats	SQL	Medium

Stack Priority Queue

No	Title	Solution	Difficulty
71	Simplify Path	Rust	Medium
84	Largest Rectangle in Histogram	Rust	Hard
150	Evaluate Reverse Polish Notation	Rust	Medium
155	Min Stack	Rust	Easy
215	Kth Largest Element in an Array	Rust	Medium
218	The Skyline Problem	Rust	Hard
224	Basic Calculator	Rust	Medium
225	Implement Stack using Queues	Rust	Medium
227	Basic Calculator II	Rust	Medium
232	Implement Queue using Stacks	Rust	Easy
263	Ugly Number	Rust	Easy
264	Ugly Number II	Rust	Medium
313	Super Ugly Number	Rust	Medium
332	Reconstruct Itinerary	Rust	Medium
341	Flatten Nested List Iterator	Rust	Medium
347	Top K Frequent Elements	Rust	Medium
373	Find K Pairs with Smallest Sums	Rust	Medium
385	Mini Parser	Rust	Medium
388	Longest Absolute File Path	Rust	Medium
394	Decode String	Rust	Medium
503	Next Greater Element II	Rust	Medium
857	Minimum Cost to Hire K Workers	Rust	Hard
1221	Split a String in Balanced Strings	Rust	Easy

String

No	Title	Solution	Difficulty
3	Longest Substring Without Repeating Characters	Rust	Medium
5	Longest Palindromic Substring	Rust	Medium
6	ZigZag Conversion	Rust	Easy
9	Palindrome Number	Rust	Easy
12	Integer to Roman	Rust	Medium
13	Roman to Integer	Rust	Easy
14	Longest Common Prefix	Rust	Easy
20	Valid Parentheses	Rust	Easy
22	Generate Parentheses	Rust	Medium
28	Implement strStr()	Rust	Easy
30	Substring with Concatenation of All Words	Rust	Hard
32	Longest Valid Parentheses	Rust	Hard
38	Count and Say	Rust	Easy
49	Group Anagrams	Rust	Medium
58	Length of Last Word	Rust	Easy
65	Valid Number	Rust	Easy
68	Text Justification	Rust	Hard
76	Minimum Window Substring	Rust	Hard
87	Scramble String	Rust	Hard
115	Distinct Subsequences	Rust	Hard
125	Valid Palindrome	Rust	Easy
131	Palindrome Partitioning	Rust	Medium
132	Palindrome Partitioning II	Rust	Hard
151	Reverse Words in a String	Rust	Medium
159	Longest Substring with At Most Two Distinct Characters	Rust	Hard
161	One Edit Distance	Rust	Medium
168	Excel Sheet Column Title	Rust	Easy
171	Excel Sheet Column Number	Rust	Easy
179	Largest Number	Rust	Medium
186	Reverse Words in a String II	Rust	Medium
187	Repeated DNA Sequences	Rust	Medium
205	Isomorphic Strings	Rust	Easy
208	Implement Trie (Prefix Tree)	Rust	Medium
211	Add and Search Word - Data structure design	Rust	Medium
212	Word Search II	Rust	Hard
214	Shortest Palindrome	Rust	Hard
241	Different Ways to Add Parentheses	Rust	Medium
242	Valid Anagram	Rust	Easy
246	Strobogrammatic Number	Rust	Easy
247	Strobogrammatic Number II	Rust	Medium
248	Strobogrammatic Number III	Rust	Hard
249	Group Shifted Strings	Rust	Medium
266	Palindrome Permutation	Rust	Easy
267	Palindrome Permutation II	Rust	Medium
271	Encode and Decode Strings	Rust	Medium
273	Integer to English Words	Rust	Medium
290	Word Pattern	Rust	Easy
293	Flip Game	Rust	Easy
294	Flip Game II	Rust	Medium
301	Remove Invalid Parentheses	Rust	Hard
316	Remove Duplicate Letters	Rust	Hard
336	Palindrome Pairs	Rust	Hard
340	Longest Substring with At Most K Distinct Characters	Rust	Hard
344	Reverse String	Rust	Easy
345	Reverse Vowels of a String	Rust	Easy
358	Rearrange String k Distance Apart	Rust	Hard
383	Ransom Note	Rust	Easy
387	First Unique Character in a String	Rust	Easy
392	Is Subsequence	Rust	Medium
395	Longest Substring with At Least K Repeating Characters	Rust	Medium
459	Repeated Substring Pattern	Rust	Easy
557	Reverse Words in a String III	Rust	Easy
567	Permutation in String	Rust	Medium
647	Palindromic Substrings	Rust	Medium
680	Valid Palindrome II	Rust	Easy
796	Rotate String	Rust	Easy
804	Unique Morse Code Words	Rust	Easy
819	Most Common Word	Rust	Easy
884	Uncommon Words from Two Sentences	Rust	Easy
929	Unique Email Addresses	Rust	Easy
1002	Find Common Characters	Rust	Easy
1047	Remove All Adjacent Duplicates In String	Rust	Easy
1071	Greatest Common Divisor of Strings	Rust	Easy
1092	Shortest Common Supersequence	Rust	Hard
1100	Find K-Length Substrings With No Repeated Characters	Rust	Medium
1160	Find Words That Can Be Formed by Characters	Rust	Easy
1347	Minimum Number of Steps to Make Two Strings Anagram	Rust	Medium
1528	Shuffle String	Rust	Easy
1629	Slowest Key	Rust	Easy
1689	Partitioning Into Minimum Number Of Deci-Binary Numbers	Rust	Medium

Tree

No	Title	Solution	Difficulty
94	Binary Tree Inorder Traversal	Rust	Medium
95	Unique Binary Search Trees II	Rust	Medium
96	Unique Binary Search Trees	Rust	Medium
98	Validate Binary Search Tree	Rust	Medium
99	Recover Binary Search Tree	Rust	Hard
100	Same Tree	Rust	Easy
101	Symmetric Tree	Rust	Easy
102	Binary Tree Level Order Traversal	Rust	Easy
103	Binary Tree Zigzag Level Order Traversal	Rust	Medium
104	Maximum Depth of Binary Tree	Rust	Easy
105	Construct Binary Tree from Preorder and Inorder Traversal	Rust	Medium
106	Construct Binary Tree from Inorder and Postorder Traversal	Rust	Medium
107	Binary Tree Level Order Traversal II	Rust	Easy
108	Convert Sorted Array to Binary Search Tree	Rust	Medium
109	Convert Sorted List to Binary Search Tree	Rust	Medium
110	Balanced Binary Tree	Rust	Easy
111	Minimum Depth of Binary Tree	Rust	Easy
112	Path Sum	Rust	Easy
113	Path Sum II	Rust	Medium
114	Flatten Binary Tree to Linked List	Rust	Medium
124	Binary Tree Maximum Path Sum	Rust	Hard
129	Sum Root to Leaf Numbers	Rust	Medium
144	Binary Tree Preorder Traversal	Rust	Medium
145	Binary Tree Postorder Traversal	Rust	Hard
156	Binary Tree Upside Down	Rust	Medium
173	Binary Search Tree Iterator	Rust	Medium
199	Binary Tree Right Side View	Rust	Medium
222	Count Complete Tree Nodes	Rust	Medium
226	Invert Binary Tree	Rust	Easy
230	Kth Smallest Element in a BST	Rust	Medium
250	Count Univalue Subtrees	Rust	Medium
255	Verify Preorder Sequence in Binary Search Tree	Rust	Medium
257	Binary Tree Paths	Rust	Easy
270	Closest Binary Search Tree Value	Rust	Easy
272	Closest Binary Search Tree Value II	Rust	Hard
298	Binary Tree Longest Consecutive Sequence	Rust	Medium
314	Binary Tree Vertical Order Traversal	Rust	Medium
331	Verify Preorder Serialization of a Binary Tree	Rust	Medium
333	Largest BST Subtree	Rust	Medium
337	House Robber III	Rust	Medium
366	Find Leaves of Binary Tree	Rust	Medium
437	Path Sum III	Rust	Medium
617	Merge Two Binary Trees	Rust	Easy
654	Two Sum IV - Input is a BST	Rust	Easy
1026	Maximum Difference Between Node and Ancestor	Rust	Medium
1145	Binary Tree Coloring Game	Rust	Medium
1305	All Elements in Two Binary Search Trees	Rust	Medium
1373	Maximum Sum BST in Binary Tree	Rust	Hard