#include <bits/stdc++.h>
using namespace std;
int val[200005];
int main() {
  int n;
  scanf("%d", &n);
  int sum = 0;
  for (int i = 0; i < n; i++) {
    scanf("%d", &val[i]);
    sum += val[i];
  }
  int cnt = 0;
  for (int i = 0; i < n; i++) {
    if (val[i] * n == sum) cnt++;
  }
  printf("%d\n", cnt);
  for (int i = 0; i < n; i++) {
    if (val[i] * n == sum) printf("%d ", i + 1);
  }
}
