#include <iostream>

int& foo()
{
	int a = 0;
	return a;
}

int& bar()
{
	int a = 10;
	return a;
}

int main()
{
	int& k = foo();
	std::cout << k << std::endl;
	bar();
	std::cout << k << std::endl;
	return 0;
}