#include <iostream>
#include <vector>
using namespace std;
typedef long long ll;
ll INF = 1000000000000000;
struct segment_tree{
    int n; vector<ll> seg;
    segment_tree(){}
    segment_tree(int sz){n = sz; seg.resize(2*n);}
    segment_tree(vector<ll> v){
        n = v.size(); seg.resize(2*n);
        for(int i=0;i<n;i++) seg[i + n] = v[i];
        for(int i=n - 1;i>0;i--) seg[i] = max(seg[i<<1],seg[i<<1|1]);
    }
    void init(int sz){n = sz; seg.resize(2*n);}
    void update(int p,ll val){
        for(seg[p += n] = val;p>1;p>>=1) seg[p>>1] = max(seg[p],seg[p^1]);
    }
    ll query(int l,int r){
        ll res = -INF;
        for(l += n,r += n; l<r;l>>=1,r>>=1){
            if(l&1) res = max(res,seg[l++]);
            if(r&1) res = max(res,seg[--r]);
        }
        return res;
    }
    int bin(int l,ll x){//seg.query(l,r - 1)<x,seg,qeury(l,r)>=x, return r;
        int le = l,ri = n;
        while(ri - le>1){
            int mid = (le + ri)/2;
            if(query(l,mid)>=x) ri = mid;
            else le = mid; 
        }
        return ri;
    }
    void clear(){for(int i=0;i<2*n;i++) seg[i] = 0;}
};

int a[300010];
int main(){
    int i,n; cin >> n;
    for(i=0;i<n;i++) cin >> a[i];
    segment_tree seg(n + 1);
    vector<int> l(n),r(n);
    for(i=0;i<n;i++){
        l[i] = seg.query(0,a[i]) + 1;
        seg.update(a[i],l[i]);
    }
    seg.clear();
    for(i=n - 1;i>=0;i--){
        r[i] = seg.query(a[i],n + 1) + 1;
        seg.update(a[i] - 1,r[i]);
    }
    int len = seg.query(0,n + 1);
    vector<int> used;
    for(i=0;i<n;i++){
        if(l[i] + r[i]==len + 1) used.push_back(a[i]);
    }
    int k = used.size();
    vector<bool> le(k),ri(k);
    int mx = -1;
    for(i=0;i<k;i++){
        if(mx<used[i]) le[i] = true;
        else le[i] = false;
        mx = max(mx,used[i]);
    }
    int mn = n + 1;
    for(i=k - 1;i>=0;i--){
        if(used[i]<mn) ri[i] = true;
        else ri[i] = false;
        mn = min(mn,used[i]);
    }
    vector<int> ans;
    for(i=0;i<k;i++){
        if(le[i] && ri[i]) ans.push_back(used[i]);
    }
    cout << ans.size() << endl;
    for(int x:ans) cout << x << " ";
    cout << endl;
}