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#include <cstdio>
#include <algorithm>

int possible_order[1000000];

int main()
{
  int n;
  scanf("%d", &n);

  for (int i = 0; i < n; i++)
    scanf("%d", &possible_order[i]);

  printf ("%d\n2\n1 2\n", 2 - std::min<int>(std::count(possible_order, possible_order + n, 1), 2));
}