Relationship of the this pointer and (non-)const member function

Let's see the example first.

class A {
public:
A() { a = 0; }
int& Get() { return a; }
void Test() const { this->Get(); }
void Test() { this->Get(); }
private:
int a;
};

int main() {
A obj;
obj.Test();
return 0;
}

Obviously, it is wrong due to the const member function and int& return value. However, how to modify it? The accurate version should be like this:

class A {
public:
A() { a = 0; }
int& Get() { return a; }
void Test() const { ((A *)this)->Get(); }
void Test() { this->Get(); }
private:
int a;
};

int main() {
A obj;
obj.Test();
return 0;
}

Through this modification, we can conclude that the type of this pointer is quite different. As we can see, in the const version, the object pointed by this pointer cannot be modified (type: const
A *), while in the common version, it can be modified (type: A *).