#include <iostream>
 
using std::cout;
using std::endl;
 
class Foo {
    int m_i;
public:
    Foo() : m_i(0) { cout << "Foo(@" << (void*)this << ") ctor" << endl; }
    Foo(int i) : m_i(i) { cout << "Foo(" << i << "@" << (void*)this << ") ctor" << endl; }
    ~Foo() { cout << "Foo(" << m_i << "@" << (void*)this << ") dtor" << endl;}
 
    Foo(const Foo& rhs) : m_i(rhs.m_i) { cout << "Copying(" << m_i << "@" << (void*)&rhs << ") to Foo(@" << (void*)this << ")" << endl; }
    Foo& operator = (Foo rhs) { m_i = rhs.m_i; cout << "op=ing(" << m_i << "@" << (void*)&rhs << ") to Foo(@" << (void*)this << ")" << endl; }
 
    Foo operator + (Foo rhs) {
        Foo result(m_i);
        cout << (void*)(&result) << " = " << (void*)this << " + " << (void*)(&rhs) << endl;
        result.m_i += rhs.m_i;
        return result;
    }
 
    operator int() const { return m_i; }
};
 
class Bar {
    int m_i;
public:
    Bar() : m_i(0) { cout << "Bar(@" << (void*)this << ") ctor" << endl; }
    Bar(int i) : m_i(i) { cout << "Bar(" << i << "@" << (void*)this << ") ctor" << endl; }
    ~Bar() { cout << "Bar(" << m_i << "@" << (void*)this << ") dtor" << endl;}
 
    Bar(const Bar& rhs) : m_i(rhs.m_i) { cout << "Copying(" << m_i << "@" << (void*)&rhs << ") to Bar(@" << (void*)this << ")" << endl; }
    Bar& operator = (const Bar& rhs) { m_i = rhs.m_i; cout << "op=ing(" << m_i << "@" << (void*)&rhs << ") to Bar(@" << (void*)this << ")" << endl; }
 
    Bar operator + (const Bar& rhs) {
        Bar result(m_i);
        cout << (void*)(&result) << " = " << (void*)this << " + " << (void*)(&rhs) << endl;
        result.m_i += rhs.m_i;
        return result;
    }
 
    operator int() const { return m_i; }
};
 
int main(int argc, const char** argv) {
    {
        Foo a(5), b(10), c;
        c = a + b;
        cout << (int)c << endl;
    }
 
    cout << endl << "Now let's do it properly." << endl << endl;
 
    {
        Bar a(5), b(10), c;
        c = a + b;
        cout << (int)c << endl;
    }
 
    return 0;
}

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