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//Piotr Golda
#include <iostream>

int main()
{
	std::ios_base::sync_with_stdio(false);
	int n{};
	int x{};
	int ones{ 0 };
	std::cin >> n;
	for (auto i = 0; i < n; ++i)
	{
		std::cin >> x;
		if (x == 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\n1 2\n";
	return 0;
}