#include <bits/stdc++.h>
using namespace std;
const int maxn = 110;
int n, _sum;
int arr[maxn];
vector<int> v;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  cin >> n;
  for (register int i = 1; i <= n; ++i) cin >> arr[i], _sum += arr[i];
  int mx_party = arr[1] / 2, mn_sum = _sum / 2 + 1, tmp_sum = arr[1];
  for (register int i = 2; i <= n; ++i) {
    if (arr[i] > mx_party) continue;
    v.push_back(i);
    tmp_sum += arr[i];
    if (tmp_sum >= mn_sum) break;
  }
  if (tmp_sum < mn_sum) {
    puts("0");
    return 0;
  }
  cout << v.size() + 1 << '\n'
       << "1"
       << " ";
  for (register int i = 0; i < v.size(); ++i) cout << v[i] << " ";
  cout << '\n';
  return 0;
}
