/* -*- coding: utf-8 -*-
 *
 * 1188.cc:  No.1188 レベルX門松列 - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

const int MAX_N = 100000;
const int INF = 1 << 30;

/* typedef */

/* global variables */

int as[MAX_N], bs[MAX_N], dp[MAX_N];
int ls0[MAX_N], ls1[MAX_N], ls2[MAX_N], ls3[MAX_N];

/* subroutines */

int lis(int n, int as[], int ids[]) {
  fill(dp, dp + n, INF);

  int m = 0;
  for (int i = 0; i < n; ++i) {
    ids[i] = lower_bound(dp, dp + n, as[i]) - dp;
    dp[ids[i]] = as[i];
    if (m < ids[i]) m = ids[i];
  }

  return m + 1;
}

/* main */

int main() {
  int n;
  scanf("%d", &n);
  for (int i = 0; i < n; i++)
    scanf("%d", as + i), bs[i] = -as[i];

  lis(n, as, ls0);
  lis(n, bs, ls1);

  reverse(as, as + n), reverse(bs, bs + n);
  lis(n, as, ls2);
  lis(n, bs, ls3);

  int maxl = 0;
  for (int i = 0; i < n; i++) {
    int l = max(min(ls0[i], ls2[n - 1 - i]), min(ls1[i], ls3[n - 1 - i]));
    if (maxl < l) maxl = l;
  }

  printf("%d\n", maxl);
  return 0;
}