I am stucked on the following code for constructors and destructors which I don't understand the result.one of the value should be 7 and how come there are four numbers? help appreciated. 

```
  class Package
  {
       private:
       int value;
public:
    Package()
    {
        value=7;
        cout<<value<<endl;
    }
    Package(int v)
    {
        value=v;
        cout<<value<<endl;
    }
    ~Package()
    {
        cout<<value<<endl;
    }
  };
  int main()
  {
     Package obj1(4);
     Package obj2();
     Package obj3(2);
     return 0;
  }

```

in console prompt it displays 

```
4
2
2
4

```