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#include <iostream>

int main()
{
	int n, a;
	int ones = 0;

	std::cin >> n;
	while (n--)
	{
		std::cin >> a;
		if (a == 1)
		{
			ones++;
		}
	}

	if (ones == 0)
	{
		std::cout << "2\n";
	}
	else if (ones == 1)
	{
		std::cout << "1\n";
	}
	else
	{
		std::cout << "0\n";
	}
	std::cout << "2\n";
	std::cout << "1 2\n";

    return 0;
}