Structures - functions and structures - Arrays of structures - structures within structures, Structures containing arrays. Files - Input & Output, sequential & random access. Basic concepts of object oriented programming - class, objects, constructors and destructors, inheritance

1. C++
Structures
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2. Sructure
 Structure is a collection of variables of different data types under a single
name. It is similar to a class in that, both holds a collection of data of
different data types.
 Structure definition
struct tagname
{
data variable name 1
data variable name 2
………………………………..
………………………………..
};
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3. Array of structure
 Structure is collection of different data type. An object of
structure represents a single record in memory, if we want more than one
record of structure type, we have to create an array of structure or object.
struct struct-name
{
datatype var1;
datatype var2;
- - - - - - - - - -
- - - - - - - - - -
datatype varN;
};
struct-name obj [ size ];
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4. Files-Input & Output
 C++ comes with libraries which provides us many ways for performing input
and output.
 In C++ input and output is performed in the form of sequence of bytes or
more commonly known as streams.
 Input Stream: If the direction of flow of bytes is from device(for example:
Keyboard) to the main memory then this process is called input.
 Output Stream: If the direction of flow of bytes is opposite, i.e. from main
memory to device( display screen ) then this process is called output.
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5. Sequential and Random acess
 Sequential Access: The computer system reads or writes information to the
file sequentially, starting from the beginning of the file and proceeding step
by step.
 It is faster than random access.
 Random Access: The computer system can read or write information
anywhere in the data file.
 We can search through it and find the data we need more easily.
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6. Object oriented programmings(Oops)
 Object-Oriented Programming is a methodology or paradigm to design a
program using classes and objects.
 It simplifies the software development and maintenance by providing some
concepts.
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7. Basic concepts of Oops
 Object:
 Any entity that has state and behavior is known as an object.
 For example: chair, pen, table, keyboard, bike etc. It can be physical and logical.
 Class:
 Collection of objects is called class.
 It is a logical entity.
 It is a user defined data type.
class class name {
access_specifier_1:
member1;
access_specifier_2:
member2;
...
} object names;
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8. Basic concepts of Oops
 Class member function definitions
 Inside of the class definition
class class_name
{
private:
declarations;
public:
function_declaration(parameters)
{
function_body;
}
};
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9. Basic concepts of Oops
 Outside of the class definition
return_type class_name::function_name(parameters)
{
function_body;
}
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10. Basic concepts of Oops
 Data Abstraction:
 Data abstraction is a concept which hides the background details and represents
only the needed information to the outside world.
 Data Encapsulation:
 It is a technique which combines both data members and functions, operates on
that data in a single unit known as a class.
 Constructors:
 Constructor is a member function with the same name as the name of a class.
 It is used to initialize the objects of that class.
 They don’t have any return type.
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11. Basic concepts of Oops
 Types of constructor
 Default Constructor
 A constructor without any parameters is called a default constructor.
 Every instance of the class will be initialized to the same values.
 Parameterized Constructor
 A constructor with at least one parameter is called a parametrized constructor.
 parametrized constructor is that you can initialize each instance of the class
with a different value.
 Copy Constructor
 The constructor which creates an object by copying variables from another
object is called a copy constructor.
 It is to initialize a new instance to the values of an existing instance.
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12. Basic concepts of Oops
 Destructor:
 Destructor is a member function which destructs or deletes an object.
 A destructor has the same name as the class, preceded by a tilde (~).
 Rules for Destructor:
 Do not accept arguments.
 Do not return a value (or void).
 Inheritance:
 It is basically a method which provides a way that capabilities and properties from
one class to come into another class.
 We can form a new class from an existing class.
 Here the new class is called as the derived class and the existing class i.e. the class
from which the new class is derived is called as the base class.
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13. Basic concepts of Oops
 Types of inheritance
 Single Inheritance: In single inheritance, a class is allowed to inherit from only
one class. i.e. one sub class is inherited by one base class only.
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14.  Multiple Inheritance: Multiple Inheritance is a feature of C++ where a class can
inherit from more than one classes. i.e. one sub class is inherited from more than
one base classes.
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15.  Multilevel Inheritance: In this type of inheritance, a derived class is created from
another derived class.
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16.  Hybrid (Virtual) Inheritance: Hybrid Inheritance is implemented by combining
more than one type of inheritance.
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17.  Hierarchical Inheritance: In this type of inheritance, more than one sub class is
inherited from a single base class. i.e. more than one derived class is created from
a single base class.
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