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

int main() {
  ios_base::sync_with_stdio(0);
  int n;
  cin >> n;
  int ones = 0;
  for (int i = 0; i < n; ++i) {
    int x;
    cin >> x;
    ones += (x == 1);
  }
  cout << max(2-ones,0) << "\n2\n1 2\n";
}