#include <bits/stdc++.h>
using namespace std;
int inf = 1e9;
const int N = 1e5 + 3;
int a[N];
multiset<pair<int, int>> al, mnset;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  int n;
  cin >> n;
  for (int i = 1; i <= n; i++) {
    cin >> a[i];
    if (i > 1) al.insert({a[i], i});
  }
  mnset.insert({a[1], 1});
  for (int i = 2; i < n; i++) {
    pair<int, int> k = {a[i], i};
    al.erase({a[i], i});
    auto it = al.begin();
    if ((it->first < a[i]) && (mnset.begin()->first < a[i])) {
      cout << "3\n"
           << (mnset.begin()->second) << " " << i << " " << (it->second);
      return 0;
    }
    auto tt = --mnset.end();
    auto tal = --al.end();
    if ((tt->first) > a[i] && tal->first > a[i]) {
      cout << "3\n" << (tt->second) << " " << i << " " << (tal->second);
      return 0;
    }
    mnset.insert({a[i], i});
  }
  cout << "0";
}
