#include <bits/stdc++.h>

using namespace std;

struct Initializer {
  Initializer() {
    cin.tie(0);
    ios::sync_with_stdio(0);
    cout << fixed << setprecision(15);
  }
} initializer;

template<typename T> inline istream& operator>>(istream &s, vector<T> &v) {
  for (T &t : v) s >> t;
  return s;
}

template<typename T> inline ostream& operator<<(ostream &s, const vector<T> &v) {
  for (const T &t : v) s << t << endl;
  return s;
}

template<typename T> inline T min(vector<T>& v) {return *min_element(v.begin(), v.end());}

template<typename T> inline T max(vector<T>& v) {return *max_element(v.begin(), v.end());}

template<typename T> inline int min_element(vector<T>& v) {return min_element(v.begin(), v.end()) - v.begin();}

template<typename T> inline int max_element(vector<T>& v) {return max_element(v.begin(), v.end()) - v.begin();}

template<typename T> inline void sort(vector<T>& v) {sort(v.begin(), v.end());}

template<typename T, typename Function> inline void sort(vector<T>& v, Function func) {sort(v.begin(), v.end(), func);}

template<typename T> inline void rsort(vector<T>& v) {sort(v.rbegin(), v.rend());}

template<typename T> inline void reverse(vector<T>& v) {reverse(v.begin(), v.end());}

template<typename T> inline void unique(vector<T>& v) {v.erase(unique(v.begin(), v.end()), v.end());}

template<typename T> inline void nth_element(vector<T>& v, int n) {nth_element(v.begin(), v.begin() + n, v.end());}

template<typename T> inline bool next_permutation(vector<T>& v) {return next_permutation(v.begin(), v.end());}

template<typename T> inline int find(vector<T>& v, T t) {return find(v.begin(), v.end(), t) - v.begin();}

template<typename T> inline int in(vector<T> v, T t) {return find(v, t) != (int)v.size();}

template<typename T> inline int lower_bound(vector<T>& v, T t) {return lower_bound(v.begin(), v.end(), t) - v.begin();}

template<typename T> inline int upper_bound(vector<T>& v, T t) {return upper_bound(v.begin(), v.end(), t) - v.begin();}

template<typename T> inline T accumulate(const vector<T>& v, function<T(T, T)> func = plus<T>()) {return accumulate(v.begin(), v.end(), T(), func);}

template<typename T> inline void adjacent_difference(vector<T>& v) {adjacent_difference(v.begin(), v.end(), v.begin());}

template<typename T> inline void adjacent_difference(vector<T>& v, vector<T>& u) {adjacent_difference(v.begin(), v.end(), u.begin());}

template<typename T> inline void partial_sum(vector<T>& v, vector<T>& u) {partial_sum(v.begin(), v.end(), u.begin());}

template<typename T> inline T inner_product(vector<T>& v, vector<T>& u) {return inner_product(v.begin(), v.end(), u.begin(), T(0));}

template<typename T> inline int count(const vector<T>& v, T t) {return count(v.begin(), v.end(), t);}

template<typename T, typename Function> inline int count_if(const vector<T>& v, Function func) {return count_if(v.begin(), v.end(), func);}

template<typename T, typename Function> inline void remove_if(vector<T>& v, Function func) {v.erase(remove_if(v.begin(), v.end(), func), v.end());}

template<typename T, typename Function> inline bool any_of(vector<T> v, Function func) {return any_of(v.begin(), v.end(), func);}

template<typename T> inline vector<T> subvector(vector<T>& v, int a, int b) {return vector<T>(v.begin() + a, v.begin() + b);}

template<typename T> inline int kinds(const vector<T>& v) {return set<T>(v.begin(), v.end()).size();}

template<typename T> inline void iota(vector<T>& v) {iota(v.begin(), v.end(), T());}

int n;
vector<int> a;
unordered_map<int, bool> mem;

bool solve(int bit) {
  if (mem.count(bit)) return mem[bit];
  for (int i = 0; i < n; ++i) {
    if (bit & (1 << i)) continue;
    for (int j = i + 1; j < n; ++j) {
      if (bit & (1 << j)) continue;
      if (a[i] == a[j]) continue;
      for (int k = j + 1; k < n; ++k) {
        if (bit & (1 << k)) continue;
        if (a[i] == a[k] || a[j] == a[k]) continue;
        if (max({a[i], a[j], a[k]}) != a[j] && min({a[i], a[j], a[k]}) != a[j]) continue;
        if (!solve(bit ^ (1 << i) ^ (1 << j) ^ (1 << k))) {
          if (bit == 0) cout << i << " " << j << " " << k << endl;
          return mem[bit] = true;
        }
      }
    }
  }
  return mem[bit] = false;
}

int main() {
  cin >> n;
  a.resize(n);
  cin >> a;
  solve(0);
  if (!mem[0]) cout << -1 << endl;
}