#include <iostream>
#include <algorithm>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <numeric>
#include <bitset>
#include <cmath>

static const int MOD = 1000000007;
using ll = long long;
using u32 = unsigned;
using u64 = unsigned long long;
using namespace std;

template<class T> constexpr T INF = ::numeric_limits<T>::max()/32*15+208;



int main() {
    int n;
    cin >> n;
    vector<int> A(n);
    for (auto &&i : A) scanf("%d", &i);
    vector<int> lis(n, INF<int>);
    vector<int> l(n), r(n), li(n), ri(n);
    for (int i = 0; i < n; ++i) {
        int x = lower_bound(lis.begin(),lis.end(), A[i]) - lis.begin();
        l[i] = x;
        lis[x] = A[i];
    }
    fill(lis.begin(),lis.end(), INF<int>);
    for (int i = n - 1; i >= 0; --i) {
        int x = lower_bound(lis.begin(),lis.end(), A[i]) - lis.begin();
        r[i] = x;
        lis[x] = A[i];
    }
    fill(lis.begin(),lis.end(), -INF<int>);
    for (int i = 0; i < n; ++i) {
        int x = lower_bound(lis.begin(),lis.end(), A[i], greater<>()) - lis.begin();
        li[i] = x;
        lis[x] = A[i];
    }
    fill(lis.begin(),lis.end(), -INF<int>);
    for (int i = n - 1; i >= 0; --i) {
        int x = lower_bound(lis.begin(),lis.end(), A[i], greater<>()) - lis.begin();
        ri[i] = x;
        lis[x] = A[i];
    }
    int ans = 0;
    for (int i = 0; i < n; ++i) {
        ans = max({ans, min(l[i], r[i]), min(li[i], ri[i])});
    }
    cout << ans << "\n";
    return 0;
}