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#include <cstdio>

int ones;

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