Page 52 - DCAP404 _Object Oriented Programming

Unit 2: Beginning of OOP Language

11. The ……………… statement causes the program flow to exit the body of the while loop. Notes
12. The do-while loop displays the ……………………. value of digit, increases its value by 1.

2.5 Scope Resolution Operator

C++ is also a block-structured language. We know that the same variable name can be used to
have different meanings in different blocks. The scope of a variable extends from the point of its
declaration till the end of the block, containing the declaration. A variable declared inside a
block is said to be local to that block. Blocks in C++ are often nested. For example the following
style is common:
. . . . .

. . . . .
{
int x=10;
. . . . .
. . . . .
{
int x=1;

. . . . .
. . . . .
}
. . .
. .
}
The declaration in an inner block hides a declaration of the same variable in the outer block. C++
resolves this problem by introducing a new operator :: called the scope resolution operator.
This can be used to uncover a hidden variable. It takes the following format:

::variable_name
This operator allows access to the global version of a variable.
Program illustrating the use of :: is given below:
# include <iostream.n>
int m=10; //globalm
main()
{

int m=20 //m is redeclared; local to main
{
int n=m;
int m=30; //m is declared again
cout << “we are in innerblock \n”;

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