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

const int MAXN = 1000*1000;
int degs[MAXN];

int main() {
  ios_base::sync_with_stdio(0);
  long long n;
  cin >> n;
  int ones = 0;
  for (int i = 0; i < n; i++) {
    cin >> degs[i];
    if (degs[i] == 1) ones++;
  }
  
  cout << 2 - min(ones, 2) << endl;
  cout << 2 << endl;
  cout << 1 << " " << 2 << endl;

  return 0;
}