17 Lecture

What is the syntax for overloading the assignment operator in C++? A) operator = () B) operator () C) operator () D) operator += () Answer: A Which of the following is a valid signature for an overloaded assignment operator that takes a reference to the class object as a parameter? A) MyClass operator=(MyClass& obj) B) void operator=(const MyClass& obj) C) MyClass& operator=(const MyClass& obj) D) void operator=(MyClass& obj) Answer: C What is the return type of an overloaded assignment operator? A) void B) the class type C) int D) bool Answer: B How is the overloaded assignment operator invoked in C++? A) using the = operator B) using the copy constructor C) using the constructor D) using the destructor Answer: A What is the purpose of overloading the assignment operator in C++? A) to allow objects of a class to be assigned values using the = operator B) to allow objects of a class to be compared using the == operator C) to allow objects of a class to be initialized using the constructor D) to allow objects of a class to be destroyed using the destructor Answer: A Which of the following is true about the copy constructor and the assignment operator? A) they both take a reference to the class object as a parameter B) they both return a reference to the class object C) they both perform a shallow copy of the object's data members D) they both perform a deep copy of the object's data members Answer: D What is the difference between the copy constructor and the assignment operator? A) the copy constructor creates a new object, while the assignment operator modifies an existing object B) the copy constructor takes a const reference to the object, while the assignment operator takes a non-const reference C) the copy constructor performs a deep copy of the object, while the assignment operator performs a shallow copy D) the copy constructor returns a reference to the object, while the assignment operator returns void Answer: A How do you avoid issues with self-assignment when overloading the assignment operator? A) by checking for self-assignment using the == operator B) by using a copy constructor to create a new object and then assigning it to the existing object C) by checking for self-assignment using the this pointer D) by using a swap function to swap the contents of the object with a temporary object Answer: D Which of the following is a common practice when overloading the assignment operator? A) returning a copy of the object from the function B) returning a reference to the object from the function C) using dynamic memory allocation to perform a deep copy of the object's data members D) using the default implementation of the operator provided by the compiler Answer: C Which of the following is true about the return type of the overloaded assignment operator? A) it must be a built-in type such as int or bool B) it can be any user-defined type C) it must be the same type as the class being overloaded D) it can be a different type from the class being overloaded Answer: C

What is the purpose of overloading the assignment operator? Answer: The purpose of overloading the assignment operator is to allow an object to be assigned values of the same class or a compatible data type, just like any other built-in data type. How do you overload the assignment operator? Answer: The assignment operator can be overloaded by defining a member function that takes a reference to the class as a parameter and returns a reference to the same class. What is the default behavior of the assignment operator? Answer: The default behavior of the assignment operator is to perform a shallow copy of the object's data members. What is the difference between a shallow copy and a deep copy? Answer: A shallow copy copies only the pointer values of an object's data members, while a deep copy creates new memory for the copied object's data members and copies the values. What is the syntax for overloading the assignment operator? Answer: The syntax for overloading the assignment operator is: kotlin Copy code class MyClass { public: MyClass& operator=(const MyClass& other) { // assignment logic here return *this; } }; What is the return type of the overloaded assignment operator? Answer: The return type of the overloaded assignment operator is a reference to the class, denoted by MyClass& in the above example. Can the assignment operator be overloaded as a friend function? Answer: Yes, the assignment operator can be overloaded as a friend function, which allows access to private data members. What is the copy-and-swap idiom and how does it relate to overloading the assignment operator? Answer: The copy-and-swap idiom is a design pattern used to implement the assignment operator by creating a temporary copy of the object and then swapping the temporary with the original object. This technique can simplify the code required to overload the assignment operator. What is the difference between the assignment operator and the copy constructor? Answer: The assignment operator is used to assign one object to another, while the copy constructor is used to create a new object with the same values as an existing object. When should the assignment operator be overloaded? Answer: The assignment operator should be overloaded whenever a class has dynamically allocated memory or non-static data members that need to be copied over during assignment.