#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  int mas[n];
  for (int i = 0; i < n; i++) {
    cin >> mas[i];
  }
  int d = 0;
  int t = 0;
  for (int i = 0; i < n; i++) {
    if (mas[i] - d == 1) {
      t++;
      d = mas[i];
    }
  }
  if (!d) {
    cout << "0";
    return 0;
  }
  cout << t << endl;
  d = 0;
  for (int i = 0; i < n; i++) {
    if (mas[i] - d == 1) {
      d = mas[i];
      cout << 2000 + i + 1 << " ";
    }
  }
}
