#include <bits/stdc++.h>
using namespace std;
long long gcd(long long a, long long b) {
  if (b == 0) return a;
  a %= b;
  return gcd(b, a);
}
long long power(long long x, long long y, long long md = 1000000007) {
  long long res = 1;
  x %= md;
  while (y > 0) {
    if (y & 1) res = (res * x) % md;
    x = (x * x) % md;
    y = y >> 1;
  }
  return res % md;
}
bool sortbysec(const pair<long long, long long> &a,
               const pair<long long, long long> &b) {
  return (a.second < b.second);
}
int32_t main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  long long n;
  cin >> n;
  long long sum = 0, arr[n];
  for (long long i = 0; i < n; i++) {
    cin >> arr[i];
    sum += arr[i];
  }
  if (arr[0] > sum / 2) {
    cout << 1 << '\n';
    cout << 1 << '\n';
    return 0;
  }
  long long sum1 = arr[0];
  std::vector<long long> v;
  v.push_back(1);
  for (long long i = 1; i < n; i++) {
    if (arr[0] >= (2 * arr[i])) {
      sum1 += arr[i];
      v.push_back(i + 1);
    }
  }
  if (sum1 > (sum / 2)) {
    cout << v.size() << '\n';
    for (long long j = 0; j < v.size(); j++) {
      cout << v[j] << " ";
    }
    cout << '\n';
  } else {
    cout << 0 << '\n';
  }
  return 0;
}
