#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  vector<int> v(n);
  int sum = 0;
  for (int i = 0; i < n; i++) {
    cin >> v[i];
    sum += v[i];
  }
  int req = sum / 2 - v[0] + 1;
  vector<pair<int, int> > v1;
  for (int i = 1; i < n; i++) {
    if (v[i] <= v[0] / 2) v1.push_back(make_pair(v[i], i));
  }
  vector<int> v2;
  if (req > 0)
    for (int j = 0; j < v1.size(); j++) {
      req -= v1[j].first;
      v2.push_back(v1[j].second + 1);
      if (req <= 0) break;
    }
  if (req > 0)
    cout << 0 << endl;
  else {
    cout << v2.size() + 1 << endl;
    cout << "1 ";
    for (int i = 0; i < v2.size(); i++) cout << v2[i] << " ";
    cout << endl;
  }
  return 0;
}
