What is out put of C++ code?

Code
  1. class base

  2. {

  3.   public:

  4.          virtual void display(int i = 10)

  5.          {

  6.            cout<<"Base class display with i = "<<i<<endl;

  7.          }

  8.  

  9. };

  10.  

  11. class derived : public base

  12. {

  13.   public:

  14.           void display(int i = 20)

  15.          {

  16.            cout<<"Derived class display with i = "<< i <<endl;

  17.          }

  18.  

  19. };

  20.  

  21. int main(int argc, char *argv[])

  22. {

  23.      base *bptr = new derived;

  24.      bptr->display();

  25.        

  26.       return 0;

  27. }

  28.  
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Questions by ak.nextptr   answers by ak.nextptr

Showing Answers 1 - 12 of 12 Answers

Vip

  • May 1st, 2012
 

Derived class display with i = 10

Shobhit Chaturvedi

  • May 12th, 2012
 

dervie class function display

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saum almas

  • May 30th, 2012
 

Derived class display with i = 10

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Deepak

  • Jun 13th, 2012
 

Derived class display with i=10 because in virtual functions do pass the default arguments if you are passing then made both versions of function with same default argument

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Mahesh

  • Jun 20th, 2012
 

Derived class display method with i=20, because assigning derived object to base class reference. so derived class display method will call

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Teodor

  • Aug 6th, 2012
 

It indeed displays "Derived class i=10". What happens is that through polymorphism, the base * obj = new derived() object can have access to the body of the overridden method, but its signature containing the default value for the "i" parameter is taken from the base class. That's because of the run-time vtable mechanism: the function is called for a base object, but the vtable fetches the implementation for the overridden one, from the derived class. Hence the odd output.

abhimanyu

  • Aug 9th, 2012
 

it will be 20

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reddy-

  • Apr 10th, 2013
 

Overriding function default argument takes more precedence ,Hence based class default argument 10 will be initialized to i.So i value holds 10 will be printed for this call with derived count statement.

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rohit suri

  • Sep 11th, 2014
 

Base class display method will called

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