In C++, which function can be used to test whether the end of a file (EOF) has been reached?
- checkEOF()
- testEnd()
- eof()
- isTerminated()
The eof() function is used to test if the end-of-file (EOF) has been reached on a file stream in C++. It returns true if the EOF flag for the stream is set. The other options are not standard functions for this purpose in C++.
If class B is a friend of class A, this means that class B can access the _______ members of class A.
- public
- mutable
- private
- static
When one class is declared as a friend of another class, it means the friend class can access the private and protected members of the class it befriends. It doesn't relate to static or mutable specifically and isn't limited by the public access specifier.
You're working with a loop structure that performs several operations...
- Use a conditional statement to execute the operation.
- Run the operation in a separate thread.
- Move the operation outside the loop.
- Cache the result of the operation for reuse.
By using a conditional statement, the computationally expensive operation can be executed only when necessary, rather than on every loop iteration. This ensures that the operation is only performed when required, saving computational resources and improving overall efficiency.
In a large-scale project involving network communication, what considerations might influence the design and use of custom exception classes to handle errors like network failures and message format issues?
- Granularity of error information.
- Easy debugging and logging.
- Ensuring exceptions don't introduce additional overhead in communication.
- Making network retries for every exception.
In large-scale networked applications, exceptions must be both descriptive and efficient. Custom exception classes can provide fine-grained information about the type of error, which can aid in debugging and remediation. However, the design should ensure that these exceptions don't add significant overhead to the system. It's a balance between providing enough information for diagnosis and ensuring efficient runtime behavior.
How can you prevent an object of a C++ class from being copied?
- Use private constructors
- Make the class abstract
- Declare the copy constructor as private
- Use an interface
By declaring the copy constructor (and the assignment operator) as private, you ensure that they cannot be invoked from outside the class, effectively preventing the creation of a copy of an object of the class. This is a common technique for the Singleton pattern.
Which keyword is used to define a template in C++?
- class
- public
- private
- template
The template keyword is used to define templates in C++. Templates allow functions and classes to operate with generic types, enabling more flexible and reusable code structures.
Consider a scenario where you're building a game that involves a character navigating through a maze with multiple levels. How might the break statement be used effectively in this context?
- To immediately exit the game.
- To move to the next level when the exit point is reached.
- To pause the game for a short period.
- To restart the current level.
The break statement is used to exit a loop prematurely. In the context of the game, when the character reaches an exit point of the maze, the loop processing the current level's moves can be exited using the break statement, effectively moving to the next level.
In C++, to ensure that a derived class does not override a method of a base class, the method in the base class should be declared as _______.
- final
- constant
- private
- static
In C++, when a base class wants to prevent its method from being overridden in the derived classes, it declares that method as final. This ensures that the method retains its original functionality without any modifications.
In C++, when a parameter is passed by value, what exactly is being passed to the function?
- Original value
- Memory address
- Reference
- Copy of the original value
When parameters are passed by value in C++, a copy of the original value is provided to the function. This means the function operates on this copy, and the original data remains unchanged outside the function scope.
Indirect recursion involves a function calling another function that eventually calls the original function, forming a _______.
- cycle
- chain
- tree
- grid
Indirect recursion forms a cycle where function A calls function B (or a series of functions), and eventually, one of those functions calls back to function A. This loop of function calls forms the cycle characteristic of indirect recursion.
Which of the following containers in the Standard Template Library (STL) allows duplicate elements and keeps them in sorted order?
- std::vector
- std::set
- std::unordered_set
- std::multiset
The std::multiset container in the STL allows duplicate elements and keeps them in a sorted order based on their values. Unlike std::set, which ensures each element is unique, std::multiset allows storage of multiple instances of equivalent elements.
How does tail recursion differ from non-tail recursion in terms of performance?
- Tail recursion uses more memory.
- Non-tail recursion is always faster.
- Tail recursion can be optimized by compilers to iterative loops.
- They perform the same in all aspects.
Tail recursion is a form of recursion where the recursive call is the last operation in the function. Because of this, compilers can optimize tail recursive functions by transforming them into iterative loops, thus potentially improving performance and reducing stack usage.