C++ Programming - Constructors and Destructors - Discussion

#include<iostream>
using namespace std;
class complex
{
public:
int num1,num2;
complex ()
{

}
complex (int a, int b)
{
num1=a;
num2=b;
}
};
int main()
{
complex obj;
obj=complex(4,5);
cout<<obj.num1<<" "<<obj.num2<<endl;
obj=complex(7,8);
cout<<obj.num1<<" "<<obj.num2;
return 0;
}

Here, Constructor is called two times.

class A
{
public:
int a;
A(){ a = 5; }
};
int main()
{
A a;
a.a = 6;
new (&a) A();
cout << a.a; // prints 5
}

Does this count as creating a new object?

Otherwise, D is correct.

But it depends upon the how many objects we are created. On that depends how many times constructor be called.

Life time of the object means from when it is created till the end of it's scope. Whenever an object gets created, the constructor is called. Since the question implies that it is a single object, hence constructor will be called only once in the lifetime of that object.

Anyone please work it out, I didn't get this.