In the context of operator overloading, the expression a + b is equivalent to _______.
- a.add(b)
- a.operator+(b)
- a.plus(b)
- a.combine(b)
Operator overloading allows operators to be redefined and used where one or both of the operands are of a user-defined class. In the context of C++, the expression a + b where the + operator is overloaded can be reinterpreted as a.operator+(b). This allows developers to specify the behavior of the + operator for user-defined types.
You are developing a financial application where precision is crucial. Which arithmetic operation could potentially introduce errors due to floating-point representation?
- Addition
- Division
- Multiplication
- Subtraction
While all floating-point arithmetic can introduce precision errors due to the nature of their representation, division is particularly notorious because it can generate repeating fractional components that might not be accurately represented in binary floating-point. This can lead to small errors that accumulate in financial calculations.
Can a friend function of a class access the private members of that class?
- Only if the function is defined inside the class
- No, it can't
- Yes, it can
- Only if the class has no protected members
Friend functions are specially designated functions that are allowed to access the private and protected members of a class. This is their primary purpose. Although they can breach the encapsulation principle, they're useful in scenarios where certain external functions require closer integration with a class's internals.
What is the purpose of a pure virtual function in C++?
- To provide default functionality
- To force derived classes to provide an implementation
- To enhance runtime performance
- To prevent method overloading
A pure virtual function in C++ is declared using "= 0" and doesn't have an implementation in the base class. It's a way to ensure that derived classes provide their own implementation of the function, effectively making the base class abstract. This ensures a consistent interface.
What does the term “Diamond Problem” refer to in the context of C++ inheritance?
- Multiple inheritance ambiguity
- Memory leak in inheritance
- Abstract base class issue
- Diamond-shaped class structure
The "Diamond Problem" arises due to multiple inheritance when a particular class is accessible through multiple paths, often causing ambiguity. For instance, if two base classes A and B have the same method and a derived class inherits both A and B, there's ambiguity on which method to call if not overridden in the derived class.
How does the short-circuit evaluation work in logical operators?
- Sequentially
- Left-to-right
- Both operands
- None required
Short-circuit evaluation refers to the evaluation of logical expressions in a left-to-right manner, stopping as soon as the outcome is determined. For instance, in the logical AND operation (&&), if the left operand is false, the right operand won't even be evaluated because the entire expression is already false.
In C++, which keyword is used to declare an abstract class?
- virtual
- volatile
- pure
- abstract
An abstract class in C++ is a class that cannot be instantiated and is meant to be inherited by other classes. It's declared using the virtual keyword, especially when a virtual function is set to 0, making it a pure virtual function, thus making the class abstract.
A function that calls itself directly or indirectly is known as a _______ function.
- recursive
- iterative
- overloaded
- main
A function that calls itself, either directly or by calling another function that eventually results in the original function being called again, is termed recursive.
The result of dividing two integers in C++ is always a(n) _______.
- float
- char
- integer
- boolean
In C++, when two integers are divided, the result is always an integer. If there's any fractional part, it gets truncated. For instance, 5 divided by 2 results in 2, not 2.5. To obtain a floating-point result, one or both operands should be a floating-point type.
A template that takes another template as a parameter is known as a _______.
- template class
- meta-template
- function template
- inheritance template
A meta-template is a template that takes another template as its parameter. This advanced concept allows for more abstraction and flexibility in template programming.
You're reviewing a C++ codebase and notice that a function processing large data structures is passed its arguments by value, potentially causing unnecessary copies and overhead. What might be a more efficient way to pass these structures without modifying the original data?
- Passing by pointer
- Passing by reference
- Using lambda functions
- Using std::move
Passing arguments by reference allows functions to access the original memory location without creating a copy, leading to more efficient memory usage. While passing by pointer can achieve a similar outcome, it requires manual dereferencing. Passing by reference is a more idiomatic solution in C++ for this use case.
The goto statement can only jump to labels within the same _______.
- function
- file
- scope
- class
The goto statement in C++ can only jump to labels within the same function. Jumping between functions or other scopes would introduce significant complexity and is not allowed.