#include <bits/stdc++.h>


using namespace std;
typedef long long ll;

#define REP(i,n) for(int i=0; i<int(n); i++)
#define FOR(i,m,n) for(int i=int(m); i<int(n); i++)
#define ALL(obj) (obj).begin(),(obj).end()
#define VI vector<int>
#define VP vector<pair<int,int>>
#define VPP vector<pair<int,pair<int,int>>>
#define VLL vector<long long>
#define VVI vector<vector<int>>
#define VVLL vector<vector<long long>>
#define VC vector<char>
#define VS vector<string>
#define VVC vector<vector<char>>
#define VB vector<bool>
#define VVB vector<vector<bool>>
#define fore(i,a) for(auto &i:a)
typedef pair <int, int> P;
template<typename T> using min_priority_queue = priority_queue<T, vector<T>, greater<T>>;
template<class T> bool chmax(T &a, T b) { if (a < b) { a = b; return true; } return false; }
template<class T> bool chmin(T &a, T b) { if (a > b) { a = b; return true; } return false; }

const int  INF = 1 << 30 - 1;
const ll INFL = 1LL << 60;
const ll mod = 998244353;


vector<int> longest_increasing_subsequence(const vector<int> &v) {
	int n = v.size();
	vector<int> dp(n, INF);
	int m = 0;
	VI res(n);
	for (int i = 0; i < n; i++) {
		*lower_bound(dp.begin(), dp.end(), v[i]) = v[i];
		m = max(m, (int)(lower_bound(dp.begin(), dp.end(), v[i]) - dp.begin()));
		res[i] = m;
	}
	return res;
}


int main(){

	int n;
	cin >> n;

	VI a(n);
	VI b(n);
	REP(i, n) {
		cin >> a[i];
		b[i] = -a[i];
	}

	VI c = longest_increasing_subsequence(a);
	VI d = longest_increasing_subsequence(b);

	reverse(ALL(a));
	reverse(ALL(b));
	VI cc = longest_increasing_subsequence(a);
	VI dd = longest_increasing_subsequence(b);
	reverse(ALL(cc));
	reverse(ALL(dd));

	int ans = 0;
	REP(i, n) {
		ans = max(ans, min(c[i], cc[i]));
	}
	REP(i, n) {
		ans = max(ans, min(d[i], dd[i]));
	}
	cout << ans << endl;

}