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++.
Which loop is NOT compatible with the break statement in C++?
- for loop
- do-while loop
- while loop
- None, all loops support break
All loops in C++ (for, while, and do-while) support the break statement. The break statement is a control flow statement that can be used to exit a loop prematurely when a specific condition is met, irrespective of the loop's primary condition.
Which year was the C++ programming language introduced?
- 1970
- 1980
- 1983
- 1995
C++ was introduced in 1983 by Bjarne Stroustrup as an enhancement to the C language.
The syntax to declare a pure virtual function is to follow the function declaration with _______.
- '= 0'
- 'virtual'
- 'override'
- '= 1'
In C++, a pure virtual function is declared by assigning 0 in its declaration. The syntax is virtual function_name() = 0;. It indicates that the function doesn't have a body in this class and must be implemented in any non-abstract derived class.
What happens to the control flow of a program when the break statement is encountered inside a while loop?
- The program exits
- The while loop terminates and control moves to the next statement after the loop
- The loop skips to the next iteration
- The loop starts from the beginning
When a break statement is encountered inside a while loop, the loop terminates immediately and the control moves to the next statement following the loop, regardless of the loop's condition.
You are developing a game where numerous conditions dictate the character's state (e.g., running, jumping, idle, etc.). To manage these states efficiently, which approach might be preferable?
- Use multiple if-else statements
- Use a state pattern
- Use global variables
- Implement recursion
The State Pattern allows an object to change its behavior when its internal state changes. This would be ideal for game character states as it encapsulates state-specific behaviors and transitions, making the code more organized, scalable, and easy to extend with new states.
Which function is used to open a file in C++?
- openFile()
- create()
- open()
- initiateFile()
The open() function is used in C++ to open a file. It is a member function of the file stream classes (like fstream, ifstream, ofstream). By providing the filename and mode, a user can access or modify the contents of a file.
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.
What is the impact of using a friend function on encapsulation in C++?
- It enhances it.
- It doesn't affect it at all.
- It undermines it.
- It strengthens the class hierarchy.
Friend functions can access the private and protected members of a class. This can lead to a breach in encapsulation as they can potentially expose or modify class internals outside the usual member function framework. This undermines the very purpose of encapsulation.
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.