#include <bits/stdc++.h>
int as[200000];
int total = 0;
int N;
std::vector<int> good;
int main() {
  std::cin >> N;
  for (int i = 0; i < N; i++) {
    std::cin >> as[i];
    total += as[i];
  }
  for (int i = 0; i < N; i++) {
    if (as[i] * N == total) {
      good.push_back(i);
    }
  }
  std::cout << good.size() << std::endl;
  for (int i = 0; i < good.size(); i++) {
    if (i > 0) {
      std::cout << " ";
    }
    std::cout << good[i] + 1;
  }
  std::cout << std::endl;
  return 0;
}
