C++ Programming - OOPS Concepts - Discussion

I cannot understand the concept of singleton class I think it can be virtual class.

Nice example @Rajeesh.

In singleton class, what about the variable. Is there we use private constructor?

How can we say the given class is singleton not?

If it is singleton, explain others?

Singleton set is used for only one instance of the class.

Singleton means only one instance or object at a time can be created.

Singleton set example:

public class singleton();
{
private static singleton instance;
private singleton()
{

}

Public static singleton instance (this is one and only one way to obtain any instance of the singleton set).
{
get
{
if(instance==null)
{
instanece = new singleton(); (memory will be allocated only on first call to the 'instance' property)
}
return instance;
}
}

Only single class can be inherited, no multiple inheritance can take place here.

Please explain in this question in details.

What is friend class? Explain?

I too didn't understand this singleton class.