#include <bits/stdc++.h>
using namespace std;
int main() {
  int a[100000 * 2 + 10];
  int n;
  long long c = 0;
  cin >> n;
  for (int i = 0; i < n; i++) cin >> a[i], c += a[i];
  vector<int> v;
  for (int i = 0; i < n; i++)
    if (a[i] * n == c) v.push_back(i);
  cout << v.size() << endl;
  for (int i = 0; i < v.size(); i++) cout << v[i] + 1 << " ";
  return 0;
}
