#include <iostream>
using namespace std;
 
int giid = 0;
 
class animal {
public:
	int id;
	int iid;
	animal(int _id = 0) {
		cout << "construindo um animal..." << endl;
		id = _id;
		iid = giid++;
	}
 
};
 
class gato {
public:
	int id, iid;
	gato(animal a) {
		id = a.id;
		iid = giid++;
		cout << "construtor chamado automaticamente, meaw" << endl;
	}
};
 
int main() {
    animal a;
	gato xano = a;
 
	cout << "instance id do animal " << a.iid << endl;
	cout << "instance id do xano " << xano.iid << endl;
	return 0;
}

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