#include <bits/stdc++.h>
using namespace std;
template <typename T, typename Compare>
vector<int> LongestIncreasingSubsequence(vector<T> &A, Compare comp) {
    int N = (int)A.size();
    vector<T> DP;
    vector<int> nxt(N, N);
    vector<int> mem(N);
    T inf;
    if (comp(0, numeric_limits<T>::max()))
        inf = numeric_limits<T>::min();
    else
        inf = numeric_limits<T>::max();
    auto comp2 = [&](T l, T r) { return !comp(l, r); };
    for (int i = N - 1; i >= 0; i--) {
        auto it = upper_bound(DP.begin(), DP.end(), A[i], comp2);
        int d = it - DP.begin();
        if (it == DP.end())
            DP.emplace_back(A[i]);
        else
            *it = A[i];
        mem[i] = d;
    }
    stack<int> st;
    for (int i = N - 1; i >= 0; i--) {
        while (!st.empty() && !comp(A[i], A[st.top()])) st.pop();
        if (!st.empty()) nxt[i] = st.top();
        st.emplace(i);
    }
    int len = (int)DP.size();
    vector<int> ret;
    for (int i = 0; len && i < N; i++) {
        if (mem[i] == len - 1) {
            ret.emplace_back(i);
            len--;
        }
    }
    return ret;
}

int main() {
    int n;
    cin >> n;
    vector<int> v(n);
    for (int i = 0; i < n; i++) cin >> v[i];
    auto lis_min = LongestIncreasingSubsequence(v, less<int>());
    reverse(v.begin(), v.end());
    auto lis_max = LongestIncreasingSubsequence(v, greater<int>());
    reverse(lis_max.begin(), lis_max.end());
    for (int i = 0; i < lis_max.size(); i++) lis_max[i] = n - 1 - lis_max[i];
    reverse(v.begin(), v.end());

    vector<int> ans;
    int m = lis_min.size();
    assert(int(lis_max.size()) == m);
    for (int i = 0; i < m; i++) {
        cerr << lis_min[i] << " " << lis_max[i] << '\n';
        if (lis_min[i] == lis_max[i]) {
            ans.push_back(v[lis_min[i]]);
        }
    }
    cout << ans.size() << '\n';
    for (int i = 0; i < ans.size(); i++) {
        cout << ans[i] << " \n"[i == int(ans.size()) - 1];
    }
}