Who Deletes the Engine?

1#include <iostream>
2using namespace std;
3 
4class Engine {
5public:
6    Engine() { cout << "Engine built" << endl; }
7    ~Engine() { cout << "Engine destroyed" << endl; }
8};
9 
10class Garage {
11    Engine* m_engine;
12public:
13    Garage() {
14        m_engine = new Engine();
15        cout << "Garage open" << endl;
16    }
17    ~Garage() {
18        delete m_engine;
19        cout << "Garage closed" << endl;
20    }
21    Engine* engine() const { return m_engine; }
22};
23 
24class Mechanic {
25    Engine* m_engine;
26public:
27    Mechanic(Engine* e) : m_engine(e) { cout << "Mechanic hired" << endl; }
28    ~Mechanic() { cout << "Mechanic leaves" << endl; }
29};
30 
31int main() {
32    Garage g;
33    {
34        Mechanic m1(g.engine());
35        Mechanic m2(g.engine());
36    }
37    cout << "end" << endl;
38    return 0;
39}