#include <bits/stdc++.h>
using namespace std;
int n;
int arr[101];
int first;
vector<pair<int, int>> v, v2;
int mx;
int sum;
int sum2;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  cin >> n;
  cin >> arr[0];
  first = arr[0];
  sum += first;
  sum2 += first;
  for (int i = 1; i < n; i++) {
    cin >> arr[i];
    sum += arr[i];
    if (arr[i] <= first / 2) {
      v.push_back(make_pair(arr[i], i + 1));
    }
  }
  if (first > sum / 2) {
    cout << 1 << endl;
    cout << 1;
    return 0;
  }
  sort(v.begin(), v.end());
  for (int i = 0; i < v.size() && i < n - 2; i++) {
    sum2 += v[i].first;
    if (sum2 > sum / 2) {
      cout << i + 2 << endl;
      cout << 1 << " ";
      for (int j = 0; j <= i; j++) cout << v[j].second << " \0"[j == i];
      return 0;
    }
  }
  cout << 0;
  return 0;
}
