#include <bits/stdc++.h>
using namespace std;
const int maxn = 105;
int n, a[maxn];
int main() {
  while (cin >> n) {
    int sum = 0, cnt = 0;
    vector<int> v;
    for (int i = 1; i <= n; i++) {
      cin >> a[i];
      sum += a[i];
    }
    v.push_back(1);
    cnt += a[1];
    for (int i = 2; i <= n; i++) {
      if (a[i] <= a[1] / 2) {
        cnt += a[i];
        v.push_back(i);
      }
      if (cnt >= sum / 2 + 1) {
        break;
      }
    }
    if (cnt >= sum / 2 + 1) {
      printf("%d\n", v.size());
      for (int i = 0; i < v.size(); i++) printf("%d ", v[i]);
      printf("\n");
    } else {
      cout << 0 << endl;
    }
  }
}
