#include <bits/stdc++.h>
using namespace std;
bool comp(pair<int, int> &a, pair<int, int> &b) { return a.second < b.second; }
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  int n;
  cin >> n;
  int ct;
  vector<pair<int, int>> pii;
  int mainparty;
  double seat = 0.0;
  for (int i = 0; i < n; i++) {
    cin >> ct;
    pii.push_back(make_pair(i + 1, ct));
    seat += ct;
  }
  mainparty = pii[0].second;
  seat /= 2;
  if (mainparty > seat) {
    cout << "1" << endl << "1";
    return 0;
  }
  sort(pii.begin() + 1, pii.end(), comp);
  vector<int> v;
  v.push_back(1);
  for (int i = 1; i < n && mainparty <= seat; i++) {
    if (pii[0].second >= 2 * pii[i].second) {
      mainparty += pii[i].second;
      v.push_back(pii[i].first);
    }
  }
  if (mainparty <= seat) {
    cout << "0";
    return 0;
  }
  cout << v.size() << endl;
  for (auto itr = v.begin(); itr != v.end(); itr++) {
    cout << *itr << " ";
  }
}
