Which of the following algorithms is not present in the C++ STL?
- binary_search
- find
- sort
- magic_square
The C++ STL provides a plethora of algorithms for various operations, but "magic_square" is not among them. binary_search, find, and sort are standard algorithms provided in the STL.
Which organization is responsible for maintaining the C++ language standard?
- IEEE
- IETF
- ISO/IEC
- W3C
The International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC) jointly maintain the C++ language standard. Specifically, the ISO/IEC JTC1/SC22/WG21 committee is in charge of the C++ standard's evolution.
In a multi-level inheritance scenario where multiple C++ classes are sharing methods and data, how might encapsulation and abstraction principles be applied to ensure data integrity and reduce complexity?
- Allow every class to modify the data of its base classes directly.
- Avoid using encapsulation and abstraction altogether.
- Use friend functions extensively for data access.
- Properly encapsulate data at each level and provide abstract interfaces for interactions.
In multi-level inheritance, it's essential to maintain data integrity and manage complexity. This is achieved by encapsulating data at every inheritance level, ensuring that each class exposes only what's necessary to its derived classes. Abstract interfaces further help in defining clear boundaries and interactions between classes.
What is the relationship between abstraction and interfaces in C++?
- Interfaces are concrete implementations of abstraction.
- Abstraction is achieved using only interfaces.
- Interfaces ensure abstraction but not vice versa.
- C++ does not have interfaces.
In C++, there isn't a direct concept of "interfaces" as in some other languages. However, abstract classes with only pure virtual functions can act similarly to interfaces. These ensure abstraction by forcing derived classes to provide concrete implementations, but not all abstractions need to be interfaces.
You are debugging a C++ application and find that a goto statement is causing erratic jumps and consequently, unexpected behavior. Which refactoring approach might be the most beneficial to enhance code readability and maintainability?
- Replace goto with structured loops.
- Encapsulate the goto in a function.
- Add comments explaining the goto.
- Ignore it and move on.
Using goto statements can lead to spaghetti code that's hard to maintain and debug. It's considered a best practice to avoid using goto in C++. Replacing goto with structured loops or conditionals can often make the code clearer and more maintainable. While encapsulation is a good practice in general, it doesn't address the fundamental problems associated with goto. Comments can help but don't solve the root issue.
In a real-time graphics application where performance is critical, you need to manage a dynamically-allocated array that can change size. Which of the following STL containers would be the most appropriate choice considering the balance between dynamic size management and performance?
- vector
- list
- deque
- forward_list
The STL vector is a dynamic array that provides O(1) access time for its elements. It's efficient when resizing (amortized constant time for insertions/deletions at the end), making it suitable for scenarios requiring a balance between dynamic size management and performance.
What is the impact on performance when using float versus double in mathematical calculations in C++?
- float is faster
- double is faster
- No difference
- It depends on context
While "float" may use less memory, "double" provides higher precision. The performance impact depends on the architecture and context. Some architectures are optimized for double precision, making operations as fast, if not faster, than float operations.
How does a member function differ from a regular function in C++?
- It can only be called by an object.
- It does not have a return type.
- It always has parameters.
- It cannot be defined inside a class.
A member function in C++ is associated with an object of the class and has access to the object's data members. Unlike regular functions, member functions can be called using the object of the class and can manipulate the class's attributes directly. Regular functions don't have this implicit access.
In C++, function overloading is resolved at _______.
- runtime
- declaration time
- compile-time
- execution-time
Function overloading allows multiple functions in the same scope to have the same name as long as they have different parameter lists. In C++, the appropriate overloaded function is chosen at compile-time based on the function call's arguments.
Which keyword is used in C++ to make a function virtual?
- static
- const
- virtual
- override
The keyword virtual is used in C++ to make a function virtual. When a function is declared as virtual, it can be overridden in any derived class. This allows for dynamic polymorphism, where the decision on which method version to execute is made at runtime based on the object's actual type.