Answer Posted / md. nasim ahmed

The conventional polymorphism approach can also be used to reach the desired result of handling different class object with same set of methods. But the problem is the driver (main/module) must handle the creation of type of object.
CBase *bptr=new CChild();
bptr->method1();
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The Factory design pattern ease the programming effort to write the driver program as the creation of object is handled by base class only(factory class).
CBase *bptr= CBase::make_object(chioce);

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Now refer http://sourcemaking.com/design_patterns/factory_method/cpp/1

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