Answer / swetcha

Virtual inheritance is used to avoid multiple copies of a
base class in a multiple-inherited object. However, there
are cases where multiple copies of a base are needed in a
derived class. In such cases, virtual inheritance is
intentionally avoided

Answer / rakesh kumar

whenever there are two derived class derived from same base
class,when these two derived classes derive third derived
class which contain the properties of the 1st base class
twice.virtual class is use to avoid this.

Answer / achal ubbott

The concept of virtual inheritance was evolved to avoid
ambiguity/duplication.

e.g.
class base
{
int value;
};
now we do some multiple inheritance
class A:public base {};
class B:public base {};

Now value is member to both the classes A and B.
Lets have a class C that inherits from both A and B.
class C:public A, public B {};

Now should that mean that C have 2 copies of value as its
data member? Yes and this leads to ambiguity.
So do like this

class C:virtual public A,virtual public B {};

Answer / shivachinna

virtual concept is uaed to avoid confusions with same name
of methods in super class as well as sub class.....

Answer / rama

The duplication of inherited members due to multiple paths can be avoided by making the common base class(ancestor class) as virtual base class..

FOR EXAMPLE

class A //grandparent
{
...
...
};
class B1:virtual public A //parent1
{
...
...
};
class B2:public virtual A //parent2
{
...
...
};
class C :public B1,public B2
{
... //only one copy of A
... //will be inherited
};


When a class is made a virtual base class, it take necessary care to see that only one copy of that class is inherited, regardless of how many inheritance paths exits between the virtual base class and a derived class.

Answer / sandeep mannarakkal

Virtual inheritance is used for creating an a class (portion in the derived object ) as first. Once this object portion got created then compiler insert a offset to the remaining portion of the object for identifying the virtual portions.

Answer / sharukh khan

Totally wrong answer !
you are fail man !
read some more books !


please read books guys , websites cheats you !

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0 Answers  

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0 Answers  

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0 Answers  

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0 Answers  

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5 Answers   Quark,

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1 Answers  

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0 Answers