#include <bits/stdc++.h>
using namespace std;
int main() {
  int i, j, n;
  long sum, num;
  short f[200001];
  bool a[200001];
  double aver;
  cin >> n;
  for (i = 1; i <= 200001; i++) a[i] = false;
  sum = 0;
  num = 0;
  for (i = 1; i <= n; i++) {
    cin >> j;
    f[i] = j;
    sum = sum + j;
  }
  aver = double(sum) / double(n);
  for (i = 1; i <= n; i++)
    if (double(f[i] == aver)) {
      num++;
      a[i] = true;
    }
  cout << num << endl;
  for (i = 1; i <= n; i++)
    if (a[i]) cout << i << " ";
  if (num > 0) cout << endl;
  return 0;
}
