1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
#include <cstdio>
#include <algorithm>


int main()
{
	int koleczki = 0;
	int n, t;
	scanf("%d", &n);
	for (int i = 0; i < n; i++)
	{
		scanf("%d", &t);
		if (t == 1) koleczki++;
	}

	printf("%d\n2\n1 2\n", 2 - std::min(koleczki, 2));

	return 0;
}