What is public, protected, private?

C++ Interview Questions and Answers

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What is public, protected, private?

• Public, protected and private are three access specifiers in C++.
• Public data members and member functions are accessible outside the class.
• Protected data members and member functions are only available to derived classes.
• Private data members and member functions can’t be accessed outside the class. However there is an exception can be using friend classes.

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Other Interview Questions

• What is C++?
• What is a modifier?
• What is an accessor?
• Differentiate between a template class and class template.
• When does a name clash occur?
• Define namespace.
• What is the use of ‘using’ declaration.
• What is an Iterator class?
• What is an incomplete type?
• What is a dangling pointer?
• Differentiate between the message and method.
• What is an adaptor class or Wrapper class?
• What is a Null object?
• What is class invariant?
• What do you mean by Stack unwinding?
• Define precondition and post-condition to a member function.
• What are the conditions that have to be met for a condition to be an invariant of the class?
• What are proxy objects?
• Name some pure object oriented languages.
• What is a node class?
• What is an orthogonal base class?
• What is a container class? What are the types of container classes?
• How do you write a function that can reverse a linked-list?
• What is polymorphism?
• How do you find out if a linked-list has an end? (i.e. the list is not a cycle)
• How can you tell what shell you are running on UNIX system?
• What is Boyce Codd Normal form?
• What is pure virtual function?
• Write a Struct Time where integer m, h, s are its members
• How do you traverse a Btree in Backward in-order?
• What is the two main roles of Operating System?
• In the derived class, which data member of the base class are visible?
• How do you find out if a linked-list has an end? (i.e. the list is not a cycle)
• What is the difference between realloc() and free()?
• What is function overloading and operator overloading?
• What is the difference between declaration and definition?
• What are the advantages of inheritance?
• How do you write a function that can reverse a linked-list?
• What do you mean by inline function?
• Write a program that ask for user input from 5 to 9 then calculate the average
• Write a short code using C++ to print out all odd number from 1 to 100 using a for loop
• What is public, protected, private?
• Write a function that swaps the values of two integers, using int* as the argument type.
• Tell how to check whether a linked list is circular.
• What is polymorphism?
• What is virtual constructors/destructors?
• What is the difference between an ARRAY and a LIST?
• Does c++ support multilevel and multiple inheritance?
• What is a template?
• Define a constructor - What it is and how it might be called (2 methods).
• You have two pairs: new() and delete() and another pair : alloc() and free(). Explain differences between eg. new() and malloc()
• What is the difference between class and structure?
• What is RTTI?
• What is encapsulation?
• Explain term POLIMORPHISM and give an example using eg. SHAPE object: If I have a base class SHAPE, how would I define DRAW methods for two objects CIRCLE and SQUARE
• What is an object?
• How can you tell what shell you are running on UNIX system?
• Describe PRIVATE, PROTECTED and PUBLIC – the differences and give examples.
• What is namespace?
• What do you mean by inheritance?
• What is a COPY CONSTRUCTOR and when is it called?
• What is Boyce Codd Normal form?
• What is virtual class and friend class?
• What is the word you will use when defining a function in base class to allow this function to be a polimorphic function?
• What do you mean by binding of data and functions?
• What are 2 ways of exporting a function from a DLL?
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• What is friend function?
• Which recursive sorting technique always makes recursive calls to sort subarrays that are about half size of the original array?
• What is abstraction?
• What are virtual functions?
• What is the difference between an external iterator and an internal iterator? Describe an advantage of an external iterator.
• What is a scope resolution operator?
• What do you mean by pure virtual functions?
• What is polymorphism? Explain with an example?
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• What’s the output of the following program? Why?
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• What is an HTML tag?
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• Anything wrong with this code? T *p = 0; delete p;
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• What’s the best way to declare and define global variables?
• What does extern mean in a function declaration?
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• What is the difference between char a[] = “string”; and char *p = “string”;?
• What’s the auto keyword good for?
• What is the difference between char a[] = “string”; and char *p = “string”; ?
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• What does extern mean in a function declaration?
• How do I initialize a pointer to a function?
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• I write a program in C++ that asks the user for names of students and their cooresponding midterm scores ...
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• What is a conversion constructor?
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• What is an explicit constructor?
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• Will it execute or not?
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• What methods can be overridden in Java?
• What are the defining traits of an object-oriented language?
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