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#include <cstdio>

int n, a, ones;

int main() {
	scanf("%d", &n);
	ones = 0;
	for (int i = 0; i < n; ++i) {
		scanf("%d", &a);
		ones += a == 1;
	}
	if (ones == 0) {
		printf("2\n");
	}
	else if (ones == 1) {
		printf("1\n");
	}
	else {
		printf("0\n");
	}
	printf("2\n1 2\n");
}