@T3rminal Then how would you explain size of Z in case of normal inheritance( sizeof(Z)=16
On Mon, Jul 4, 2011 at 4:08 AM, T3rminal <[email protected]> wrote: > @abc abc > 4th class= two ints from X and Y classes + one int from base class( as > this class is shared ) + 2 virtual pointers of X and Y classes. > According to your logic it should be 12 > > On Jul 3, 2:24 pm, abc abc <[email protected]> wrote: > > In the second case , the size of vptr will be added to each and every > object > > . > > 1st class = one int :4 > > 2nd class = one int +one int from base + vptr =12 > > 3rd class = one int + one int from base + vptr =12 > > 4th class =one int from each base class + one int from each of the grand > > parent +one vptr =20 > > > > On Sun, Jul 3, 2011 at 2:43 PM, himanshu kansal < > [email protected] > > > > > > > > > > > > > > > > > wrote: > > > class Base > > > { > > > public: > > > int a; > > > }; > > > > > class X: public Base > > > { > > > public: > > > int x; > > > }; > > > > > class Y: public Base > > > { > > > public: > > > int y; > > > }; > > > > > class Z:public X,public Y > > > { > > > }; > > > > > int main() > > > {cout<<sizeof(Base)<<endl; > > > cout << sizeof(X) <<endl; > > > cout << sizeof(Y) <<endl; > > > cout << sizeof(Z) <<endl; > > > } > > > o/p is 4 > > > 8 > > > 8 > > > 16... > > > which is absolutely fine..... > > > > > but the problem arises here.... > > > class Base > > > { > > > public: > > > int a; > > > }; > > > > > class X:virtual public Base > > > { > > > public: > > > int x; > > > }; > > > > > class Y:virtual public Base > > > { > > > public: > > > int y; > > > }; > > > > > class Z:public X,public Y > > > { > > > }; > > > > > int main() > > > {cout<<sizeof(Base)<<endl; > > > cout << sizeof(X) <<endl; > > > cout << sizeof(Y) <<endl; > > > cout << sizeof(Z) <<endl; > > > } > > > > > o/p is 4 > > > 12 > > > 12 > > > 20 > > > why the size is 12 and 20 for x and Z....does this is because that > > > some sort of VPTR IS maintained in the class....if yes then then what > > > does that points to.... > > > > > PS:HERE.....i am talking about virtual inheritance....NOT ABOUT > > > "VIRTUAL FUNCTIONS"... > > > > > -- > > > You received this message because you are subscribed to the Google > Groups > > > "Algorithm Geeks" group. > > > To post to this group, send email to [email protected]. > > > To unsubscribe from this group, send email to > > > [email protected]. > > > For more options, visit this group at > > >http://groups.google.com/group/algogeeks?hl=en. > > -- > You received this message because you are subscribed to the Google Groups > "Algorithm Geeks" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/algogeeks?hl=en. > > -- You received this message because you are subscribed to the Google Groups "Algorithm Geeks" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.
