#include <iostream>
    using namespace std;
 
    struct test {
        test()            { cout << "constructor" << endl; }
        test(const test&) { cout << "copy constructor" << endl; }
        test(test&&)      { cout << "move constructor" << endl; }
        ~test()           { cout << "destructor" << endl; }
    };
 
    struct nested {
        test t;
    //    nested() {}
    };
 
    auto main() -> int {
        // prints "constructor", "copy constructor" and "destructor"
        auto n = nested{};
        cout << endl;
 
        return 0;
    }
 

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