#include <bits/stdc++.h>
using namespace std;
int main() {
  long long int n, i = 0, arr[100000], count = 0;
  cin >> n;
  for (i = 0; i < n; i++) {
    cin >> arr[i];
  }
  for (i = 1; i < n; i++) {
    if (((arr[i] - arr[0]) * (arr[i] - arr[i + 1])) > 0 && i + 1 < n) {
      cout << "3" << endl;
      cout << "1"
           << " " << i + 1 << " " << i + 2 << endl;
      return 0;
    }
  }
  cout << "0" << endl;
  return 0;
}
