#include <iostream>
#include <vector>
 
using namespace std;
 
class base
{
    public:
        virtual ~base(){}
};
 
template<typename T>
class derived : public base {
	public:
	derived(const T t_){}
};
 
class myClass
{
    public:
        template<typename T>
        myClass(const T t) : data(new derived<T>(t)){}
        ~myClass(){delete data;}
    private:
        base* data;
};
 
int main() {
 
 
    vector<myClass> vec;
 
    myClass obj(22);
 
    vec.push_back(obj); // constructor is invoked and then destructor is invoked, why?
 
 
	return 0;
}

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