Scope resolution operator

:: operator allow to access global version of a variable.
C++ is a block structured language. Same variable name in different blocks have different meaning.
The scope of a variable is only limited to the block in which it is declared. 

Consider example :

Here block 2 defined in block 1. variable x defined in two blocks with different values.
The variable x holds the value 20 in block 2. if we access the value of x using scope resolution
operator it will return 10.

The general form is : 

:: variable name. 

in block 2 the statement
       cout<< x       will return value of x=20
       cout<<::x      will return value of x=10

New operator is used to allocate memory dynamically for an object. It remain in existence until it is destroyed explicitly by delete.

The syntax for New operator is:

        pointer variable = new data type;

        int *p = new int(5);

When a object is no longer needed it is destroyed to release memory space. The general form of delete is: 

        delete pointer variable

        delete p;

The endl operator causes linefeed to be inserted. It has the sane effect as using the newline character “\n”. 

For example:

cout<<“enter vaslur<<endl;

or

cout<<“enter value”<<“\n”;