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#include <bits/stdc++.h>
using namespace std;


int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  
  int n;
  cin >> n;
  
  int ones = 0;
  for (int i = 0; i < n; ++i) {
    int deg;
    cin >> deg;
    if (deg == 1)
      ++ones;
  }
  
  cout << max(0, 2 - ones) << '\n';
  cout << "2\n1 2" << '\n';
}