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#include <cstdio>

int main()
{
	int n;
	int a;
	int onesCnt = 0;

	scanf("%d", &n);
	while (n--) {
		scanf("%d", &a);
		if (a == 1) {
			onesCnt++;
		}
	}

	if (onesCnt > 2) {
		onesCnt = 2;
	}

	printf("%d\n", 2 - onesCnt);
	printf("2\n1 2\n");

	return 0;
}