#include <bits/stdc++.h>
int main() {
  int a[200001], i, n, sum = 0, num[200001], flag = 0;
  double ave = 0.0;
  scanf("%d\n", &n);
  for (i = 1; i <= n; i++) {
    scanf("%d", &a[i]);
    sum += a[i];
  }
  ave = (double)sum / n;
  for (i = 1; i <= n; i++)
    if (a[i] == ave) {
      flag++;
      num[flag] = i;
    }
  if (flag != 0) {
    printf("%d\n", flag);
    for (i = 1; i <= flag; i++) printf("%d ", num[i]);
  } else
    printf("0\n");
}
