{"id":48528,"date":"2024-04-15T22:42:35","date_gmt":"2024-04-15T22:42:35","guid":{"rendered":"https:\/\/exam.pscnotes.com\/mcq\/?p=48528"},"modified":"2024-04-15T22:42:35","modified_gmt":"2024-04-15T22:42:35","slug":"reference-variables-and-const-class-members-_____","status":"publish","type":"post","link":"https:\/\/exam.pscnotes.com\/mcq\/reference-variables-and-const-class-members-_____\/","title":{"rendered":"Reference variables and const class members _____"},"content":{"rendered":"

[amp_mcq option1=”must be assigned values in any derived class” option2=”must never be initialized in a base class” option3=”must be initialized, rather than assigned values” option4=”must not exist if a class is to be a base class” correct=”option3″]<\/p>\n

The correct answer is: C. must be initialized, rather than assigned values<\/strong>.<\/p>\n

A reference variable is a variable that stores the address of another variable. A const class member is a member of a class that cannot be modified after it has been created.<\/p>\n

When a reference variable is initialized, the address of the variable that it is referencing is stored in the reference variable. When a const class member is initialized, the value of the member is stored in the member.<\/p>\n

In C++, reference variables and const class members must be initialized, rather than assigned values. This is because reference variables and const class members cannot be reassigned. If a reference variable or const class member is assigned a value, the compiler will generate an error.<\/p>\n

Here is an example of how to initialize a reference variable:<\/p>\n

c++
\nint x = 10;
\nint& y = x; \/\/ y is a reference to x<\/code><\/p>\n

In this example, the reference variable y<\/code> is initialized to the address of the variable x<\/code>. The value of x<\/code> cannot be changed, but the value of y<\/code> can be changed. For example, the following code will change the value of y<\/code>, but it will not change the value of x<\/code>:<\/p>\n

c++
\ny = 20;<\/code><\/p>\n

Here is an example of how to initialize a const class member:<\/p>\n

c++
\nclass C {
\npublic:
\n const int x = 10;
\n};<\/code><\/p>\n

In this example, the const class member x<\/code> is initialized to the value 10. The value of x<\/code> cannot be changed, even if the object of type C<\/code> is modified. For example, the following code will not compile:<\/p>\n

c++
\nC c;
\nc.x = 20; \/\/ error: cannot modify const member `x`<\/code><\/p>\n","protected":false},"excerpt":{"rendered":"

[amp_mcq option1=”must be assigned values in any derived class” option2=”must never be initialized in a base class” option3=”must be initialized, rather than assigned values” option4=”must not exist if a class is to be a base class” correct=”option3″]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[683],"tags":[],"class_list":["post-48528","post","type-post","status-publish","format-standard","hentry","category-object-oriented-programming-using-c-plus-plus","no-featured-image-padding"],"yoast_head":"\nReference variables and const class members _____<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/exam.pscnotes.com\/mcq\/reference-variables-and-const-class-members-_____\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" 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