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#include <cstdio>
int n, x, ones;
int main() {
  scanf("%d", &n);
  for (int i=0; i<n; i++) {
    scanf("%d", &x);
    ones += (x == 1);
  }
  printf("%d\n", (ones >= 2 ? 0 : (2 - ones)));
  printf("2\n1 2\n");
  return 0;
}