#include <bits/stdc++.h>
using namespace std;
struct TData {
  int St, Ind;
};
TData Party[110];
bool compare(TData a, TData b) { return (a.St < b.St); }
int main() {
  int N;
  cin >> N;
  int Seats = 0;
  for (int i = 0; i < N; i++) {
    cin >> Party[i].St;
    Party[i].Ind = i + 1;
    Seats += Party[i].St;
  }
  sort(Party + 1, Party + N, compare);
  Party[N].St = 30000;
  int Coal = Party[0].St;
  int Cur = 1;
  while (Party[Cur].St <= (Party[0].St / 2)) {
    Coal += Party[Cur].St;
    Cur++;
  }
  if (Coal * 2 <= Seats)
    cout << 0;
  else {
    cout << Cur << endl;
    for (int i = 0; i < Cur; i++) cout << Party[i].Ind << ' ';
  }
  return 0;
}
