#include <bits/stdc++.h>
using namespace std;
void solve() {
  long long int N;
  cin >> N;
  vector<long long int> vec(N), ans;
  for (int i = 0; i < (N); i++) cin >> vec[i];
  ;
  long long int sum = vec[0], mine = vec[0];
  ans.push_back(1);
  long long int K = 1;
  for (long long int i = 1; i < N; i++) {
    sum += vec[i];
    if (2 * vec[i] <= vec[0]) {
      mine += vec[i];
      K++;
      ans.push_back(i + 1);
    }
  }
  if (2 * mine > sum) {
    cout << K << endl;
    for (int i = 0; i <= K - 1; i++) cout << ans[i] << " ";
    cout << endl;
    ;
  } else
    cout << 0 << endl;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int T;
  T = 1;
  while (T--) {
    solve();
  }
  return 0;
}
