#include <bits/stdc++.h>
using namespace std;
class Task {
 public:
  int a[200005];
  void solve(istream& in, ostream& out) {
    int n;
    in >> n;
    for (int i = 0; i < n; i++) {
      in >> a[i];
    }
    long long sum = 0;
    for (int i = 0; i < n; i++) {
      sum += a[i];
    }
    multiset<int> res;
    for (int i = 0; i < n; i++) {
      if ((sum - a[i]) % (n - 1) == 0) {
        if (sum - a[i] == (n - 1) * a[i]) {
          res.insert(i + 1);
        }
      }
    }
    out << res.size() << endl;
    for (auto j = res.begin(); j != res.end(); j++) {
      out << *j << " ";
    }
  }
};
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  Task solver;
  std::istream& in(std::cin);
  std::ostream& out(std::cout);
  solver.solve(in, out);
  out.flush();
  return 0;
}
