#include <bits/stdc++.h>
using namespace std;
const int MAXN = 2000;
int n, first, x, sumAll, sum;
vector<int> cnt[101], ans;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cin >> n;
  for (int i = 0; i < n; ++i) {
    cin >> x;
    if (!i) {
      first = x;
    } else {
      cnt[x].push_back(i);
    }
    sumAll += x;
  }
  sum += first;
  ans.push_back(1);
  for (int i = first / 2; i >= 1; --i) {
    if (cnt[i].size()) {
      sum += i * cnt[i].size();
      for (int j = 0; j < cnt[i].size(); ++j) {
        ans.push_back(cnt[i][j] + 1);
      }
    }
  }
  if (sum < sumAll / 2 + 1) {
    cout << "0\n";
  } else {
    cout << ans.size() << "\n";
    for (int i = 0; i < ans.size(); ++i) {
      cout << ans[i] << " \n"[i == ans.size() - 1];
    }
  }
  return 0;
}
