#include <iostream>
#include <vector>

class Foo {
public:
	std::vector<int> data;
};

class Asd {
public:
	Foo f1;
	Foo f2;
};

std::vector<Foo> getfoos(const Asd& asd) {
	std::vector<Foo> out;
	out.push_back(asd.f1);
	out.push_back(asd.f2);
	return out;
}

int main(int argc, char** argv) {

	Asd asd;

	for (int i = 0; i < 4; i++) {
		asd.f1.data.push_back(i);
		asd.f2.data.push_back(i);
	}

	std::vector<Foo> another = getfoos(asd);
	another[0].data.clear();
	another[1].data.clear();
	std::cout << "foos length: " << asd.f1.data.size() << ", " << asd.f2.data.size() << std::endl;

	return 0;
}