Is the following code correct?

class A
{
public:
    int* m_a;
    A(int x) { m_a = new int(x);}
    ~A() {delete m_a;}
};

void f(A a)
{
    cout<<a.m_a;
}


int main()
{
    A a(1);
    f(a);
}

Yes, the value 1 is displayed.
No, there will be a compilation error
No, the program will crash

Explanation

The destructor is called twice, the first time when the function f() is exited, the second time it is called when the main() function is exited, trying to delete the memory allocated for the m_a variable again.