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#include <cstdio>
#include <iostream>
using namespace std;

int main() {
  ios_base::sync_with_stdio(0);
  int n, a;
  cin >> n;
  int j = 0;
  for (int i = 0; i < n; i++) {
    cin >> a;
    if (a == 1) {
      j++;
    }
  }
  cout << max(0, 2 - j) << endl;
  cout << 2 << endl;
  cout << "1 2" << endl;
}