#include <cmath>
#include <vector>
#include <iostream>
 
class V
{
	std::vector<int> *ex_;
 
	public: 
		V( std::vector<int>::size_type sz );
		~V();
};
 
V::V( std::vector<int>::size_type sz ) : ex_ ( new std::vector<int>( sz ) )
{
	// Why this doesn't work ??
	std::cout<< "Ex size:" <<ex_->size() << std::endl;
}
 
V::~V()
{
	delete ex_;
}
 
int main()
{
  // This works	
  std::vector<int> *myVec = new std::vector<int>(10);
  std::cout << "Vector size:" << myVec->size() << std::endl;
 
  // Why this doesn't work ??
  V v(myVec->size());
  delete myVec;
  return 0;
}

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