Online Judges

This repository contains my solutions to problems in different online judge platforms such as LeetCode, Hackerrank, etc. If you like this repository, consider giving it a star ⭐.

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1. LeetCode

LeetCode

#	Title	Solutions	Difficulty	Tag
2167	Count Operations To Obtain Zero	Solution	Easy	Math
2164	Sort Even And Odd Indices Independently	Solution	Easy	Heap, Sorting
1928	Minimum Cost To Reach Destination In Time	Solution	Hard	Graph, Dijkstra
1913	Maximum Product Difference Between Two Pairs	Solution	Easy	Array, Sort
1721	Swapping Noes In A Linked List	Solution	Medium	Linked List
1675	Minimize Deviation In Array	Solution	Hard	Heap
1672	Richest Customer Wealth	Solution	Easy	Array, Matrix
1663	Smallest String With A Given Numeric Value	Solution	Medium	String, Greedy
1658	Minimum Operations To Reduce X To Zero	Solution	Medium	Array, Sliding Window
1567	Maximum Length Of Subarray With Positive Product	Solution	Medium	Dynamic Programming, Array
1510	Stone Game IV	Solution	Hard	Dynamic Programming, Array
1463	Cherry Pickup II	Solution	Hard	Dynamic Programming
1413	Minimum Value To Get Positive Step By Step Sum	Solution	Easy	Array, Prefix Sum
1359	Count All Valid Pickup And Delivery Options	Solution	Hard	Dynamic Programming, Math
1345	Jump Game IV	Solution	Hard	Graph, BFS
1338	Reduce Array Size To The Half	Solution	Medium	Array, Sorting, Heap
1337	The K Weakest Rows In A Matrix	Solution	Easy	Array, Sorting
1305	All Elements In Two Binary Search Trees	Solution	Medium	Tree, DFS, Sorting
1291	Sequential Digits	Solution	Medium	Enumeration
1288	Remove Covered Intervals	Solution	Medium	Array, Sorting
1286	Iterator For Combination	Solution	Medium	Design, Bit Manipulation
1283	Find The Smallest Divisor Given A Threshold	Solution	Medium	Array, Binary Search
1260	Shift 2D Grid	Solution	Easy	Array, Matrix
1249	Minimum Remove To Make Valid Parentheses	Solution	Medium	Stack
1218	Longest Arithmetic Subsequence Of Given Difference	Solution	Medium	Dynamic Programming
1189	Maximum Number Of Balloons	Solution	Easy	String, Counting
1155	Number Of Dice Rolls With Target Sum	Solution	Medium	Dynamic Programming
1143	Longest Common Subsequence	Solution	Medium	Dynamic Programming
1137	N-th Tribonacci Number	Solution	Easy	Dynamic Programming
1108	Defanging an IP Address	Solution	Easy	String
1094	Car Pooling	Solution	Medium	Array, Prefix Sum
1049	Last Stone Weight II	Solution	Medium	Dynamic Programming
1047	Remove All Adjacent Duplicates In String	Solution	Easy	String
1046	Last Stone Weight	Solution	Easy	Heap
1041	Robot Bounded In Circle	Solution	Medium	String
1029	Two City Scheduling	Solution	Medium	Array, Greedy
1022	Sum Of Root To Leaf Binary Numbers	Solution	Easy	Tree, DFS
1014	Best Sight Seeing Pair	Solution	Medium	Dynamic Programming
1010	Pairs Of Songs With Total Durations Divisible By 60	Solution	Medium	Dynamic Programming
1009	Complement Of Base 10 Integer	Solution	Easy	Bit Manipulation
1007	Minimum Domino Rotations For Equal Row	Solution	Medium	Array, Greedy
1004	Max Consecutive Ones III	Solution	Medium	Array, Sliding Window
997	Find The Town Judge	Solution	Easy	Graph
994	Rotting Oranges	Solution	Medium	Array, BFS
993	Cousins In Binary Tree	Solution	Easy	Tree, BFS
991	Broken Calculator	Solution	Medium	Math, Greedy
987	Vertical Order Traversal Of A Binary Tree	Solution	Hard	Tree, DFS
983	Minimum Cost For Tickets	Solution	Medium	Dynamic Programming
980	Unique Paths III	Solution	Hard	Array, Backtracking, Matrix
977	Squares Of A Sorted Array	Solution	Easy	Array, Two Pointers, Sorting
953	Verifying An Alien Dictionary	Solution	Easy	String
946	Validate Stack Sequences	Solution	Easy	Stack
941	Valid Mountain Array	Solution	Easy	Array
931	Minimum Falling Path Sum	Solution	Medium	Dynamic Programming
923	3 Sum With Multiplicity	Solution	Medium	Array, Two Pointers
918	Maximum Sum Circular Subarray	Solution	Medium	Dynamic Programming
917	Reverse Only Letters	Solution	Easy	String, Two Pointers
897	Increasing Order Search Tree	Solution	Easy	Binary Tree, DFS
895	Super Egg Drop	Solution	Hard	Stack
887	Super Egg Drop	Solution	Hard	Dynamic Programming
877	Stone Game	Solution	Medium	Array
876	Middle Of The Linked List	Solution	Easy	Linked List
875	Koko Eating Bananas	Solution	Medium	Array, Binary Search
881	Boats To Save People	Solution	Medium	Array
871	Minimum Number Of Refueling Stops	Solution	Hard	Dynamic Programming
856	Score OF Parentheses	Solution	Medium	Stack
849	Maximize Distance To Closest Person	Solution	Medium	Array, Two Pointers
847	Shortest Path Visiting All Nodes	Solution	Hard	Graph, Bit Manipulation
827	Making A Large Island	Solution	Hard	Array, DFS
799	Champagne Tower	Solution	Medium	Dynamic Programming
767	Reorganize String	Solution	Medium	Heap
763	Partition Labels	Solution	Medium	String, Two Pointers
746	Min Cost Climbing Stairs	Solution	Easy	Dynamic Programming
740	Delete And Earn	Solution	Medium	Dynamic Programming, Array
739	Daily Temperatures	Solution	Medium	Stack
735	Asteroid Collision	Solution	Medium	Stack
733	Flood Fill	Solution	Easy	Array, DFS
714	Best Time to Buy and Sell Stock with Transaction Fee	Solution	Medium	Dynamic Programming
704	Binary Search	Solution	Easy	Array, Binary Search
703	Kth Largest Element In A Stream	Solution	Easy	Heap, Data Stream
701	Insert Into A Binary Search Tree	Solution	Medium	Tree
700	Search In A Binary Search Tree	Solution	Easy	Tree
695	Max Area Of Islands	Solution	Medium	Array, Depth First Search
682	Baseball Game	Solution	Easy	Stack
680	Valid Palindrome II	Solution	Easy	String, Two Pointers
669	Trim A Binary Search Tree	Solution	Medium	Tree, Recursion
668	Kth Smallest Number In Multiplication Table	Solution	Hard	Array, Matrix, Binary Search
662	Maximum Width Of Binary Tree	Solution	Medium	Tree, DFS
650	2 Keys Keyboard	Solution	Medium	Dynamic Programming
646	Maximum Length Of Pair Chain	Solution	Medium	Dynamic Programming
617	Merge Two Binary Trees	Solution	Easy	Tree, DFS, BFS
605	Can Place Flowers	Solution	Easy	Array, Greedy
572	Subtree Of Another Tree	Solution	Easy	Tree
567	Permutation In String	Solution	Medium	String, Two Pointers, Sliding Window
566	Reshape The Matrix	Solution	Easy	Array, Matrix
560	Subarray Sum Equals K	Solution	Medium	Array, Prefix Sum
557	Reverse Words In A String III	Solution	Easy	String
556	Next Greater Element III	Solution	Medium	Math
543	Diameter Of Binary Tree	Solution	Easy	Tree
542	Zero One Matrix	Solution	Medium	Array, Matrix, BFS
540	Single Element In A Sorted Array	Solution	Medium	Array, Binary Search
538	Convert BST To Greater Tree	Solution	Medium	Tree, Recursion
532	K Diff Pairs In An Array	Solution	Medium	Array
525	Contiguous Array	Solution	Medium	Array, Prefix Sum
520	Detect Capital	Solution	Easy	String
516	Longest Palindromic Subsequence	Solution	Medium	Dynamic Programming
509	Fibonacci Number	Solution	Easy	Dynamic Programming
503	Next Greater Element II	Solution	Medium	Stack
496	Next Greater Element I	Solution	Easy	Stack
485	Max Consecutive Ones	Solution	Easy	Array
474	Ones And Zeroes	Solution	Medium	Dynamic Programming
461	HammingDistance	Solution	Easy	Bit Manipulation
460	LFU Cache	Solution	Hard	Design
454	4 Sum II	Solution	Medium	Array
452	Minimum Number Of Arrows To Burst Balloons	Solution	Medium	Array, Sorting
450	Delete Node In A BST	Solution	Medium	Tree, BST
448	Find All Numbers Disappeared In An Array	Solution	Easy	Array
443	String Compression	Solution	Medium	String
441	Arranging Coins	Solution	Easy	Math
438	Find All Anagrams In A String	Solution	Easy	String, Sliding Window
421	Maximum XOR Of TwoNumbers In An Array	Solution	Medium	Bit Manipulation
413	Arithmetic Slices	Solution	Medium	Dynamic Programming
412	Fizz Buzz	Solution	Easy	Math
410	Split Array LargestSum	Solution	Hard	Dynamic Programming
404	Sum Of Left Leaves	Solution	Easy	Tree, DFS
402	Remove K Digits	Solution	Easy	Tree, DFS
398	Random Pick Index	Solution	Medium	Math, Reservoir Sampling, Randomized
394	Decode String	Solution	Medium	Stacks, Depth First Search
392	Is Subsequence	Solution	Easy	String, Two Pointers
389	Find The Difference	Solution	Easy	String
387	First Unique Character In A String	Solution	Easy	String
383	Ransom Note	Solution	Easy	String
382	Linked List Random Node	Solution	Medium	Randomized, Reservoir Sampling, Linked List
381	Insert Delete GetRandom O(1) Duplicates Allowed	Solution	Hard	Design, Randomized
380	Insert Delete GetRandom O(1)	Solution	Medium	Design, Randomized
378	Kth Smallest Element in a Sorted Matrix	Solution	Medium	Array, Matrix
374	Guess Number Higher Or Lower	Solution	Easy	Binary Search, Interactive
368	Largest Divisible Subset	Solution	Medium	Array
350	Intersection Of Two Arrays II	Solution	Easy	Array
349	Intersection Of Two Arrays	Solution	Easy	Array
347	Top K Frequent Elements	Solution	Medium	Heap
344	Reverse String	Solution	Easy	String
338	Counting Bits	Solution	Easy	Dynamic Programming, Bit Manipulation
337	House Robber III	Solution	Medium	Dynamic Programming, Tree
328	Odd Even Linked List	Solution	Medium	Linked List
322	Coin Change	Solution	Medium	Dynamic Programming
316	Remove Duplicate Characters	Solution	Medium	String, Greedy
312	Burst Balloons	Solution	Hard	Dynamic Programming
309	Best Time to Buy and Sell Stock with Cooldown	Solution	Medium	Dynamic Programming
303	Range Sum Query - Immutable	Solution	Easy	Dynamic Programming
295	Find Median From Data Stream	Solution	Hard	Heap
290	Word Pattern	Solution	Easy	String
289	Game Of Life	Solution	Medium	Array, Matrix
287	Find The Duplicate Number	Solution	Medium	Array, Two Pointers
283	Move Zeroes	Solution	Easy	Array
279	Perfect Squares	Solution	Medium	Dynamic Programming
278	First Bad Version	Solution	Easy	Array, Binary Search
268	Missing Number	Solution	Easy	Array, Math
264	Ugly Number II	Solution	Medium	Dynamic Programming
258	Add Digits	Solution	Easy	Math
242	Valid Anagram	Solution	Easy	String
238	Product Of Array Except Self	Solution	Medium	Array, Prefix Sum
232	Implement Queue Using Stacks	Solution	Easy	Design, Stack, Queue
230	Kth Smallest Element In A BST	Solution	Medium	Tree, DFS
228	Summary Ranges	Solution	Easy	Array
226	Invert Binary Tree	Solution	Easy	Tree
225	Implement Stack Using Queues	Solution	Easy	Stack, Queue
222	Count Complete Tree Node	Solution	Medium	Tree, DFS
221	Maximal Square	Solution	Medium	Dynamic Programming
217	Contains Duplicate	Solution	Easy	Array
213	House Robber II	Solution	Medium	Dynamic Programming
212	Word Search II	Solution	Hard	Array, Matrix, Backtracking, DFS, Trie
211	Design Add And Search Words Data Structure	Solution	Medium	Design, Trie, DFS
206	Reverse Linked List	Solution	Easy	Linked List
203	Remove Linked List Elements	Solution	Easy	Linked List
202	Happy Number	Solution	Easy	Math
201	Bitwise AND Of Numbers Range	Solution	Medium	Bit Manipulation
199	Binary Tree Right Side View	Solution	Medium	Tree, BFS
198	House Robber	Solution	Easy	Dynamic Programming
191	Number Of 1 Bits	Solution	Easy	Bit Manipulation
190	Reverse Bits	Solution	Easy	Bit Manipulation
189	Rotate Array	Solution	Easy	Array, Two Pointers
188	Best Time To Buy And Sell Stock IV	Solution	Hard	Dynamic Programming
174	Dungeon Game	Solution	Hard	Dynamic Programming
171	Excel Sheet Column Number	Solution	Easy	Math, String
169	Majority Element	Solution	Easy	Array
167	Two Sum II - Input Array Is Sorted	Solution	Easy	Array
165	Compare Version Numbers	Solution	Medium	String, Two Pointers
162	Find Peak Element	Solution	Medium	Array, Binary Search
152	Maximum Product Subarray	Solution	Medium	Dynamic Programming, Array
151	Reverse Words In A String	Solution	Medium	String
148	Sort List	Solution	Medium	Linked List, Sorting
146	LRU Cache	Solution	Medium	Design
145	Binary Tree Postorder Traversal	Solution	Easy	Tree
144	Binary Tree Preorder Traversal	Solution	Easy	Tree
142	Linked List Cycle II	Solution	Medium	Linked List, Two Pointers
141	Linked List Cycle	Solution	Easy	Linked List, Two Pointers
139	Word Break	Solution	Medium	Dynamic Programming
138	Copy List With Random Pointer	Solution	Medium	Linked List
136	Single Number	Solution	Easy	Bit Manipulation, Array
135	Candy	Solution	Hard	Array, Greedy
134	Gas Station	Solution	Medium	Array, Greedy
133	Clone Graph	Solution	Medium	Graph
131	Palindrome Partitioning	Solution	Medium	Backtracking, String
129	Sum Root To Leaf Numbers	Solution	Medium	Tree, DFS
127	Word Ladder	Solution	Hard	String, BFS
123	Best Time To Buy And Sell Stock III	Solution	Hard	Dynamic Programming
122	Best Time To Buy And Sell Stock II	Solution	Easy	Dynamic Programming
121	Best Time To Buy And Sell Stock	Solution	Easy	Dynamic Programming
120	Triangle	Solution	Medium	Dynamic Programming
118	Pascal's Triangle	Solution	Easy	Dynamic Programming
116	Populating Next Right Pointers In Each Node	Solution	Medium	Tree, BFS
108	Convert Sorted Array To Binary Search Tree	Solution	Easy	Tree
104	Maximum Depth Of Binary Tree	Solution	Easy	Tree
102	Binary Tree Level Order Traversal	Solution	Medium	Tree, BFS
101	Symmetric Tree	Solution	Easy	Tree
98	Validate Binary Search Tree	Solution	Medium	Tree
96	Unique Binary Search Trees	Solution	Medium	Dynamic Programming, Tree
95	Unique Binary Search Trees II	Solution	Medium	Tree
94	Binary Tree Inorder Traversal	Solution	Easy	Tree, Stack, DFS
91	Decode Ways	Solution	Medium	Dynamic Programming, String
88	Merge Sorted Array	Solution	Easy	Array, Two Pointer, Sorting
84	Largest Rectangle In Histogram	Solution	Hard	Stack, Array
83	Remove Duplicates From Sorted List	Solution	Easy	Linked List
82	Remove Duplicates From Sorted List II	Solution	Medium	Linked List
81	Search In Rotated Sorted Array II	Solution	Medium	Array, Binary Search
80	Remove Duplicates In Sorted Array II	Solution	Medium	Array
79	Word Search	Solution	Medium	Array, Matrix, Backtracking, DFS
78	Subsets	Solution	Medium	Bit Manipulation
74	Search A 2D Matrix	Solution	Medium	Array, Matrix
72	Edit Distance	Solution	Hard	Dynamic Programming
71	Simplify Path	Solution	Medium	Stack
70	Climbing Stairs	Solution	Easy	Dynamic Programming
67	Add Binary	Solution	Easy	Math, String, Bit Manipulation
64	Minimum Path Sum	Solution	Medium	Dynamic Programming
63	Unique Paths II	Solution	Medium	Dynamic Programming
62	Unique Paths	Solution	Medium	Dynamic Programming
61	Rotate List	Solution	Medium	Linked List, Two Pointers
59	Spiral Matrix II	Solution	Medium	Array, Matrix
56	Merge Intervals	Solution	Medium	Array
55	Jump Game	Solution	Medium	Dynamic Programming
53	Maximum Subarray	Solution	Easy	Array
45	Jump Game II	Solution	Medium	Dynamic Programming
42	Trapping Rain Water	Solution	Hard	Dynamic Programming
39	Combinations Sum	Solution	Medium	Array, Backtracking
37	Sudoku Solver	Solution	Medium	Array, Matrix, Backtracking
36	Valid Sudoku	Solution	Medium	Array, Matrix
35	Search Insert Position	Solution	Easy	Array, Binary Search
31	Next Permutation	Solution	Medium	Array, Two Pointers
26	Remove Duplicates In Sorted Array	Solution	Easy	Array
24	Swap Nodes in Pairs	Solution	Easy	Linked List
23	Merge K Sorted Lists	Solution	Hard	Linked List
21	Merge Two Sorted Lists	Solution	Easy	Linked List
20	Valid Parentheses	Solution	Easy	Stack
19	Remove Nth Node From End Of List	Solution	Medium	Linked List
13	Roman To Integer	Solution	Easy	Math
12	Integer Roman	Solution	Medium	Math
11	Container With Most Water	Solution	Medium	Array, Greedy
8	String To Integer (atoi)	Solution	Medium	String
5	Longest Palindromic Substring	Solution	Medium	String, Two Pointers
4	Median Of Two Sorted Arrays	Solution	Hard	Array, Binary Search
3	Longest Substring Without Repeating Characters	Solution	Medium	String, Sliding Window
2	Add Two Numbers	Solution	Medium	Linked List
1	Two Sum	Solution	Easy	Array