Using the sizeof operator for base class and derived class : sizeof « Operators statements « C++ Tutorial

1. C++ Tutorial
2. Operators statements
3. sizeof

#include <iostream>
#include <ostream>

class base {};
class derived : public base {};

int main()
{
  using namespace std;
  cout << sizeof(base)  << '\n';      
  cout << sizeof(derived)  << '\n';   
  base b[3];
  
  cout << sizeof(b) << '\n';          
  derived d[5];
  cout << sizeof(d) << '\n';          
}

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