#include <bits/stdc++.h>
using namespace std;
const int INF = 0x3f3f3f3f;
const long long LINF = 0x3f3f3f3f3f3f3f3f;
const int MOD = 1e9 + 7;
template <typename S, typename T>
inline bool Min(S &a, const T &b) {
  return a > b ? a = b, true : false;
}
template <typename S, typename T>
inline bool Max(S &a, const T &b) {
  return a < b ? a = b, true : false;
}
template <typename S, typename T>
inline void Adm(S &a, const T &b) {
  a = (a + b) % MOD;
  if (a < 0) a += MOD;
}
template <typename S, typename T>
inline void Mum(S &a, const T &b) {
  a = 1LL * a * b % MOD;
}
template <typename T>
inline T Gcd(T a, T b) {
  while (b) {
    T t = b;
    b = a % b;
    a = t;
  }
  return a;
}
template <typename T>
inline int BCnt(T x) {
  int cnt = 0;
  while (x) ++cnt, x &= x - 1;
  return cnt;
}
inline long long Pow(long long a, long long n) {
  long long t = 1;
  while (n) {
    if (n & 1) t = t * a % MOD;
    a = a * a % MOD, n >>= 1;
  }
  return t;
}
int a[1000];
int main() {
  int n;
  cin >> n;
  cin >> a[1];
  long long s = 0, t = a[1];
  vector<int> v;
  for (int i = 2; i <= n; ++i) {
    int x;
    cin >> a[i];
    if (a[i] <= a[1] / 2)
      t += a[i], v.push_back(i);
    else
      s += a[i];
  }
  if (t > s) {
    cout << ((int)(v).size()) + 1 << endl << 1;
    for (int x : v) cout << ' ' << x;
    cout << endl;
  } else
    cout << 0 << endl;
  return 0;
}
