| 1 | What are C++ I/O streams? C++ › I/O Streams | C++ | I/O Streams | Beginner |
| 2 | How do you improve iostream performance for large I/O? C++ › I/O Streams | C++ | I/O Streams | Advanced |
| 3 | What is the difference between std::cout, std::cerr, and std::clog? C++ › I/O Streams | C++ | I/O Streams | Beginner |
| 4 | How do you check for and handle stream errors? C++ › I/O Streams | C++ | I/O Streams | Beginner |
| 5 | How do you read a file with ifstream and write with ofstream? C++ › I/O Streams | C++ | I/O Streams | Intermediate |
| 6 | What is the difference between >> and std::getline for input? C++ › I/O Streams | C++ | I/O Streams | Intermediate |
| 7 | What is the difference between std::endl and '\n'? C++ › I/O Streams | C++ | I/O Streams | Intermediate |
| 8 | What is std::stringstream and when is it useful? C++ › I/O Streams | C++ | I/O Streams | Intermediate |
| 9 | What are stream manipulators and how are they used? C++ › I/O Streams | C++ | I/O Streams | Advanced |
| 10 | How do you overload operator<< for a custom type? C++ › I/O Streams | C++ | I/O Streams | Advanced |
| 11 | How do you efficiently copy data between two streams using Stream.CopyToAsync(), and why is this preferred over a manual byte-by-byte loop? C# › File I/O & Streams | C# | File I/O & Streams | Intermediate |
| 12 | How do you correctly implement async, cancellable file I/O using CancellationToken with FileStream operations? C# › File I/O & Streams | C# | File I/O & Streams | Advanced |
| 13 | How do you read and write an entire text file's contents using the simplest File class methods? C# › File I/O & Streams | C# | File I/O & Streams | Beginner |
| 14 | What is the difference between File.ReadAllLines() and File.ReadLines() in terms of memory usage? C# › File I/O & Streams | C# | File I/O & Streams | Beginner |
| 15 | How does the 'using' statement (or 'using' declaration) ensure a FileStream is properly closed, even if an exception occurs? C# › File I/O & Streams | C# | File I/O & Streams | Intermediate |
| 16 | How do StreamReader and StreamWriter differ from directly using a FileStream, and when would you choose them? C# › File I/O & Streams | C# | File I/O & Streams | Intermediate |
| 17 | How would you implement a custom Stream subclass to wrap another stream with additional behavior, like counting bytes read? C# › File I/O & Streams | C# | File I/O & Streams | Advanced |
| 18 | How do you use FileSystemWatcher to monitor a directory for file changes, and what are its common reliability pitfalls? C# › File I/O & Streams | C# | File I/O & Streams | Advanced |
| 19 | How would you implement memory-mapped file access using MemoryMappedFile for efficient random access to a very large file? C# › File I/O & Streams | C# | File I/O & Streams | Advanced |
| 20 | How would you implement a robust, atomic file-write operation that avoids leaving a corrupted or partially-written file if the process crashes mid-write? C# › File I/O & Streams | C# | File I/O & Streams | Advanced |
| 21 | What is the difference between byte streams (InputStream/OutputStream) and character streams (Reader/Writer) in the classic java.io package? Java › I/O & NIO | Java | I/O & NIO | Beginner |
| 22 | What are async streams in C#, and how does IAsyncEnumerable<T> differ from a regular IEnumerable<T> for handling large or slow data sources? C# › Asynchronous Programming | C# | Asynchronous Programming | Intermediate |
| 23 | What does the finally block guarantee, and when is it commonly used? C# › Exception Handling | C# | Exception Handling | Beginner |
| 24 | How do you efficiently build up a large string? C++ › Strings & string_view | C++ | Strings & string_view | Intermediate |
| 25 | How does an iterator method interact with try/finally, and when does the finally block actually execute given the method's lazy, on-demand nature? C# › Iterators & yield return | C# | Iterators & yield return | Intermediate |
| 26 | How does the IDisposable pattern and the 'using' statement help manage UNMANAGED resources that the garbage collector doesn't automatically clean up? C# › Memory & Garbage Collection | C# | Memory & Garbage Collection | Intermediate |
| 27 | How would you write a custom iterator that safely handles resource cleanup for a lazily-enumerated database cursor, ensuring the connection is closed even if enumeration is abandoned early? C# › Iterators & yield return | C# | Iterators & yield return | Advanced |