Class type to Class Type conversion using operator function

/*  Conversion from Class Type to Class Type
    using operator function
*/

#include <iostream>
#include <cstdlib>

using namespace std;

class C{
    int m;
    public:
        C(int);
        ~C();
        void show();
};

class D{
    int m;
    public:
        D(int);
        ~D();
        void show();
        operator C();
};

inline C::C(int m){
    C::m = m;
}

inline C::~C(){
    cout << "Destructor Called for C" << endl;
}

inline D::operator C(){
    return C(m);
}

inline D::D(int m){
    D::m = m;
}

inline D::~D(){
    cout << "Destructor Called for D" << endl;
}

inline void D::show(){
    cout << m << endl;
}

inline void C::show(){
    cout << m << endl;
}

int main() {
    D obj1(3);
    cout << "obj1.m = ";
    obj1.show();
    C obj2 = obj1;
    cout << "obj2.m = ";
    obj2.show();
    cin.get();
    return 0;
}