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#include <cstdio>

int main()
{
  int n; std::scanf("%i", &n);

  int ones = 0;
  for (int i = 0; i < n; i++) {
    int a; scanf("%i", &a);

    if (a == 1) {
      ones++;
      if (ones == 2) break;
    }
  }

  switch (ones) {
    case 2:
    puts("0\n2");
    puts("1 2");
    break;
    case 1:
    puts("1\n2");
    puts("1 2");
    break;
    case 0:
    puts("2\n2");
    puts("1 2");
    break;
  }
}