#include <bits/stdc++.h>
using namespace std;
double rez;
double a[210000];
vector<int> V;
void init() {
  int n;
  double s = 0;
  cin >> n;
  for (int i = 1; i <= n; i++) {
    cin >> a[i];
    s += a[i];
  }
  double ave = s / n;
  for (int i = 1; i <= n; i++) {
    if (a[i] == ave) V.push_back(i);
  }
  int m = V.size();
  cout << m << endl;
  if (!m) return;
  cout << V[0];
  if (m == 1) {
    cout << endl;
    return;
  }
  for (int i = 1; i <= m - 1; i++) cout << " " << V[i];
  cout << endl;
}
int main() {
  init();
  return 0;
}
