DSA & Coding Problems Explorer

All C# Programs — Data Structures 167 C# Programs — Strings 105 DSA — Hashing 105 DSA — Graphs 105 DSA — Arrays 105 DSA — Binary Search 105 DSA — Strings 105 C# Programs — Arrays 105 DSA — Sorting 105 DSA — Trees 105 DSA — Two Pointers 105 DSA — Dynamic Programming 105 DSA — Stacks & Queues 105 C# Programs — LINQ 104 C# Programs — Collections 103 C# Programs — OOP 103 C# Programs — Sorting 103 C# Programs — Interfaces 101 SQL Server — CTEs 101 SQL Server — Aggregates & GROUP BY 101 SQL Server — Indexes & plans 101 SQL Server — SELECT basics 101 SQL Server — WHERE & filtering 101 C# Programs — Inheritance 101 SQL Server — DDL & constraints 101 SQL Server — JOINs 101 SQL Server — T-SQL procedures 101 SQL Server — Subqueries 101

8773 problems

#	Title	Topics	Acceptance	Pts	Difficulty
2301	Second largest element	DSA — Strings dsa coding-practice	—	30	Medium	Solve
2302	Average salary by department	MongoDB — Aggregation mongodb coding-practice	—	30	Medium	Solve
2303	Functional component greeting	React — State react coding-practice	—	20	Easy	Solve
2304	Inner join employees and departments	SQL — JOINs sql coding-practice	—	30	Medium	Solve
2305	MySQL INNER JOIN employees and departments	MySQL — JOINs mysql coding-practice	—	30	Medium	Solve
2306	MySQL INNER JOIN employees and departments	SQL Server — JOINs sqlserver coding-practice	—	30	Medium	Solve
2307	PostgreSQL SELECT with ILIKE	PostgreSQL — JOINs postgresql coding-practice	—	20	Easy	Solve
2308	Print matrix rows	C# Programs — Matrix csharp coding-practice	—	20	Easy	Solve
2309	Read environment variable with default	Node.js — File System nodejs coding-practice	—	20	Easy	Solve
2310	Reverse a string	JavaScript — Strings javascript coding-practice	—	20	Easy	Solve
2311	Sum of array elements	DSA — Two Pointers dsa coding-practice	—	20	Easy	Solve
2312	Check palindrome	JavaScript — Strings javascript coding-practice	—	20	Easy	Solve
2313	Find maximum in array	DSA — Two Pointers dsa coding-practice	—	20	Easy	Solve
2314	Left join to include all employees	SQL — JOINs sql coding-practice	—	30	Medium	Solve
2315	Matrix transpose	C# Programs — Matrix csharp coding-practice	—	30	Medium	Solve
2316	Render list of items	React — State react coding-practice	—	20	Easy	Solve
2317	Reverse an array in-place	DSA — Two Pointers dsa coding-practice	—	30	Medium	Solve
2318	Sum of diagonal elements	C# Programs — Matrix csharp coding-practice	—	20	Easy	Solve
2319	Title case a sentence	JavaScript — Strings javascript coding-practice	—	30	Medium	Solve
2320	Count occurrences of element	DSA — Two Pointers dsa coding-practice	—	20	Easy	Solve
2321	Count word frequency	JavaScript — Strings javascript coding-practice	—	30	Medium	Solve
2322	Search element in matrix	C# Programs — Matrix csharp coding-practice	—	30	Medium	Solve
2323	Second largest element	DSA — Two Pointers dsa coding-practice	—	30	Medium	Solve
2324	Valid parentheses	JavaScript — Strings javascript coding-practice	—	40	Hard	Solve
2325	Average salary by department	SQL — Aggregates & GROUP BY sql coding-practice	—	30	Medium	Solve
2326	Find employees in Engineering	MongoDB — Indexing mongodb coding-practice	—	20	Easy	Solve
2327	MySQL SELECT with LIMIT	MySQL — Aggregates & GROUP BY mysql coding-practice	—	20	Easy	Solve
2328	MySQL SELECT with LIMIT	SQL Server — Aggregates & GROUP BY sqlserver coding-practice	—	20	Easy	Solve
2329	PostgreSQL SELECT with ILIKE	PostgreSQL — Aggregates & GROUP BY postgresql coding-practice	—	20	Easy	Solve
2330	Reverse a string	JavaScript — Functions javascript coding-practice	—	20	Easy	Solve
2331	Simple HTTP response handler	Node.js — HTTP nodejs coding-practice	—	30	Medium	Solve
2332	Sum of array elements	C# Programs — Mathematical Functions csharp coding-practice	—	20	Easy	Solve
2333	Sum of array elements	DSA — Hashing dsa coding-practice	—	20	Easy	Solve
2334	useState counter logic	React — Hooks react coding-practice	—	20	Easy	Solve
2335	Check palindrome	JavaScript — Functions javascript coding-practice	—	20	Easy	Solve
2336	Departments with total salary > 100000	SQL — Aggregates & GROUP BY sql coding-practice	—	40	Hard	Solve
2337	Find maximum in array	C# Programs — Mathematical Functions csharp coding-practice	—	20	Easy	Solve
2338	Find maximum in array	DSA — Hashing dsa coding-practice	—	20	Easy	Solve
2339	Find with projection	MongoDB — Indexing mongodb coding-practice	—	20	Easy	Solve
2340	useEffect fetch pattern (pseudo)	React — Hooks react coding-practice	—	30	Medium	Solve
2341	Reverse an array in-place	DSA — Hashing dsa coding-practice	—	30	Medium	Solve
2342	Reverse an array in-place	C# Programs — Mathematical Functions csharp coding-practice	—	30	Medium	Solve
2343	Title case a sentence	JavaScript — Functions javascript coding-practice	—	30	Medium	Solve
2344	Count occurrences of element	DSA — Hashing dsa coding-practice	—	20	Easy	Solve
2345	Count occurrences of element	C# Programs — Mathematical Functions csharp coding-practice	—	20	Easy	Solve
2346	Second largest element	DSA — Hashing dsa coding-practice	—	30	Medium	Solve
2347	Filter even numbers	JavaScript — Objects javascript coding-practice	—	20	Easy	Solve
2348	Find employees in Engineering	MongoDB — Embedding vs referencing mongodb coding-practice	—	20	Easy	Solve
2349	Functional component greeting	React — useEffect react coding-practice	—	20	Easy	Solve
2350	MySQL SELECT with LIMIT	MySQL — Subqueries mysql coding-practice	—	20	Easy	Solve

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Number of Islands

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