assignment operator and copy constructor

[destination]

class A
{
public:
A() {cout << "1";}
A operator=(const A&){cout << "2"; return *this;}
A (const A&) {cout << "3";}
};
int main()
{
A a1;
A a2 = a1;//line 1
a2 = a1;//line 2
}

pls explain which functions will be called in line 1 and line 2 and why??

[mush1578]

in line a2 is the object of class A and a1 ia the refrence variable
this is used in inhitence class
in which we call all the function of class without creating there obj and call these by refrence variable

[weaknessforcats]

Think about it. In Line 1 the object a2 does not exist. Therefore, a constructor will be called. In line 2 the object a2 does exist so an assignment operator will be called.

This question is in every job interview I have ever taken.