#include <bits/stdc++.h>
using namespace std;
const int N = 2e5 + 9;
int t, id, n, m, x, y, k, c, xx, yy, ans, p;
int a[N], f[N], vis[N], cu[N], b[N];
vector<int> v, adj[N];
bool fl, ok;
long long res, sum;
char ch;
string s, z;
int main() {
  scanf("%d", &n);
  scanf("%d", &p);
  int sum = p, tot = p;
  v.push_back(1);
  for (int i = 2; i <= (int)n; ++i) {
    scanf("%d", &x);
    if (x << 1 <= p) v.push_back(i), sum += x;
    tot += x;
  }
  if (sum << 1 > tot) {
    printf("%d\n", (int)v.size());
    for (auto it : v) printf("%d ", it);
  } else
    printf("%d\n", 0);
  return 0;
}
