//
// Created by yamunaku on 2020/08/22.
//

#include <bits/stdc++.h>

using namespace std;

#define rep(i, n) for(int i = 0; i < (n); i++)
#define repl(i, l, r) for(int i = (l); i < (r); i++)
#define per(i, n) for(int i = ((n)-1); i >= 0; i--)
#define perl(i, l, r) for(int i = ((r)-1); i >= (l); i--)
#define all(x) (x).begin(),(x).end()
#define MOD9 998244353
#define MOD1 1000000007
#define IINF 1000000000
#define LINF 1000000000000000000
#define SP <<" "<<
#define CYES cout<<"Yes"<<endl
#define CNO cout<<"No"<<endl
#define CFS cin.tie(0);ios::sync_with_stdio(false)
#define CST(x) cout<<fixed<<setprecision(x)

using ll = long long;
using ld = long double;
using vi = vector<int>;
using mti = vector<vector<int>>;
using vl = vector<ll>;
using mtl = vector<vector<ll>>;
using pi = pair<int, int>;
using pl = pair<ll, ll>;
template<typename T>
using heap = priority_queue<T, vector<T>, function<bool(const T, const T)>>;

int main(){
    //CFS;
    int n;
    cin >> n;
    vi a(n);
    rep(i, n) cin >> a[i];
    vi dp(n, IINF + 1);
    vi tmp1(n), tmp2(n);
    vi tmp3(n), tmp4(n);
    rep(i, n){
        int idx = lower_bound(all(dp), a[i]) - dp.begin();
        dp[idx] = a[i];
        tmp1[i] = idx;
    }
    dp = vi(n, IINF + 1);
    per(i, n){
        int idx = lower_bound(all(dp), a[i]) - dp.begin();
        dp[idx] = a[i];
        tmp2[i] = idx;
    }
    rep(i, n) a[i] = -a[i];
    dp = vi(n, IINF + 1);
    rep(i, n){
        int idx = lower_bound(all(dp), a[i]) - dp.begin();
        dp[idx] = a[i];
        tmp3[i] = idx;
    }
    dp = vi(n, IINF + 1);
    per(i, n){
        int idx = lower_bound(all(dp), a[i]) - dp.begin();
        dp[idx] = a[i];
        tmp4[i] = idx;
    }
    int ans = 0;
    rep(i, n){
        ans = max(ans, min(tmp1[i], tmp2[i]));
        ans = max(ans, min(tmp3[i], tmp4[i]));
    }
    cout << ans << endl;
    return 0;
}