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Discover answers to frequently asked questions about data structures and C++, and object-oriented programming. Explore the differences between arrays and linked lists, understand the role of constructors and destructors, and learn about encapsulation and data hiding.

TOP 20 Interview Questions in Data Structures and C++

Data structures and C++

In the realm of programming and data management, certain fundamental concepts like data structures and C++, and object-oriented programming are essential to grasp. This collection of frequently asked questions provides insights into these core topics, shedding light on their significance and usage.

Data structures are the building blocks of efficient data management, and understanding the differences between various types, such as linked lists, arrays, stacks, and queues, is crucial for designing efficient algorithms and managing data effectively.

In the world of C++, the distinction between structures and classes can be subtle but important. Structures are generally used for simple data storage, while classes allow for encapsulation, data hiding, and more complex behavior through member functions.

Constructors and destructors play a vital role in object-oriented programming, as they handle object initialization and cleanup. Learn how these special member functions impact the lifecycle of your objects and help ensure the integrity of your code.

Additionally, the dot operator serves as the gateway to accessing class members, facilitating the interaction with objects in C++.

By diving into these common questions, you’ll gain a better understanding of these fundamental programming concepts and their practical applications in building robust and efficient software solutions.

data structures and C++ interview questions

Data Structures and C++ Interview questions

Here are the top 20+ interview questions in data structures and C++.

Q1).State the different types of linked lists?

ANS. The different types of linked list includes, single linked list, double linked list and circular linked list.

Q2).List the basic operations carried out in a linked list?

ANS. The basic operation carried out in a linked list includes

  • Creation of a list
  • Insertions of a node
  • Declaration of a node
  • Modification of a node
  • Traversal of the list.
  • Q3). State the contents of a data field and a linked field in a linked list?

    ANS. The data field contains the information and the link field or the next address field contains the address of the next node in the list.

    Q4). Define a stack?

    ANS A stack is an ordered collection of elements in which insertions and deletions are restricted to one end. The end from which elements are added and/or removed is referred to as top of the stack. Stacks are also referred as “piles” and “push-down lists.

    Q5) Define a queue?

    ANS. a queue is an ordered collection of elements in which insertions and deletions are restricted to one end. The end from which elements are added and /or removed is referred to as to as the rear end, the end from which deletions are made is referred to as the front end.

    Q6) State the differences between arrays and linked list?

    ANS. Arrays: Size of any array is fixed . it is necessary to specify the number of elements in an array during declaration.
    Insertion and deletions are difficult in an array.
    It occupies less memory than a linked. List for the same number of elements.

    Linked Lists:

    Size of list is variable .it is not necessary to specify the number of elements in during declaration.
    Insertions and deletions are carried out easily.
    It occupies more memory.

    Q7) State the difference between stacks and linked lists?

    ANS. The difference between stacks and linked lists is that insertions and deletions may occur any where in a linked list but only at the top of the stack.

    Q8) State the difference between queues and linked lists.

    ANS. The difference between queues and linked lists in insertions and deletions may occur any where in a linked lists but queues insertions can be made only in the rear end and deletions can be made only in the front end.

    Q9)State the difference between a structure in C and C++?

    ANS. C Language structure: It can have only variables as members.
    They do not permit data hiding. They do not allow the datatype to be treated as built in types.

    C++structure : It can have both variables and functions as members. They permit data hiding.
    They allow the structure data type to be treated as built-in types.

    Q10) State the difference between a structure and class in c++?

    ANS. The only difference between a structure and class in c++ is that by default , the members of a class are private while , by default the members of a structure are public.

    Q11) State the difference between procedural and object oriented programming?

    ANS. Procedural programming focus on functions and data separately whereas object oriented programming ties data and functions to gather into object FOCUSES ON the interaction among the objects.

    Q12) what does the following preprocessor directive #includedo ?

    ANS)It causes the contents of the iostream .h file to be substituted for this directive before final compilation.

    Q13) What are member variables?

    ANS Variables of a class are called as member variables or data members.

    Q14) What are member function?

    ANS The functions declared inside a class are called as number functions.

    Q15). Can member data and member functions can be private?

    ANS. Yes both member data and members functions can be private.

    Q16) State the difference between a public and a private member of a class?

    ANS. A public member is accessible from outside the class where as a private member cannot be accessed from outside the class.

    Q17) What is the dot operator, and what is used for ?

    ANS. The operator is the period operator, which is used to access the member of the class.

    Q18) What is meant by data hiding?

    ANS. Insulation of data from direct access by the program is called data hiding.

    Q19)What is encapsulation?

    ANS. The process of combining data and functions in a single unit is called as encapsulation.

    Q20) Which member functions are created automatically if they are not including in the class definition?

    ANS. There are four class member functions that are created automatically .

    they are

    Default constructor

    Copy constructors

    Overload assignment operator

    Destructor

    Q21)What is the main use of constructors?

    ANS. Constructors are used for initializing member data in class.

    Q22). What is the main use of destructors?

    ANS. Destructors are used for reinitializing the objects which are initialized by constructors.

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