#include <bits/stdc++.h>
using namespace std;
const int maxn = 200005;
int n, a[maxn], total;
void solve() {
  vector<int> ans;
  for (int i = 1; i <= n; i++) {
    if (a[i] * n == total) ans.push_back(i);
  }
  cout << (int)ans.size() << endl;
  for (int i = 0; i < ans.size(); i++) {
    if (i) printf(" ");
    cout << ans[i];
  }
  cout << endl;
}
int main() {
  cin >> n;
  total = 0;
  for (int i = 1; i <= n; i++) {
    cin >> a[i];
    total += a[i];
  }
  solve();
  return 0;
}
