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#include <iostream>


int main() {

	int num_ones = 0;
	int n;
	int c;

	std::cin >> n;
	for (int i = 0; i < n; ++i) {
		if (num_ones == 2) {
			printf("0\n2\n1 2\n");
			return 0;
		}
		scanf("%d", &c);
		if (c == 1) num_ones++;
	}
	printf("%d\n2\n1 2\n", 2 - num_ones);
	return 0;
}