Constructors and Destructors - General Questions

When is a destructor called for an object created with new?

Which constructor takes no arguments?

How many destructors can a class have?

What will be the output of the program?

#include <iostream>
using namespace std;
class A {
public:
    A() { cout << "C"; }
    ~A() { cout << "D"; }
};
int main() {
    A a;
    cout << "M";
    return 0;
}

What will be the output of the program?

#include <iostream>
using namespace std;
class M {
    const int id;
public:
    M(int i) : id(i) {}
    int get() const { return id; }
};
int main() {
    M m(77);
    cout << m.get() << endl;
    return 0;
}