#include "bits/stdc++.h"
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
const int INF = 1e9;
const ll LINF = 1e18;
template<class S,class T> ostream& operator << (ostream& out,const pair<S,T>& o){ out << "(" << o.first << "," << o.second << ")"; return out; }
template<class T> ostream& operator << (ostream& out,const vector<T> V){ for(int i = 0; i < V.size(); i++){ out << V[i]; if(i!=V.size()-1) out << " ";} return out; }
template<class T> ostream& operator << (ostream& out,const vector<vector<T> > Mat){ for(int i = 0; i < Mat.size(); i++) { if(i != 0) out << endl; out << Mat[i];} return out; }
template<class S,class T> ostream& operator << (ostream& out,const map<S,T> mp){ out << "{ "; for(auto it = mp.begin(); it != mp.end(); it++){ out << it->first << ":" << it->second; if(mp.size()-1 != distance(mp.begin(),it)) out << ", "; } out << " }"; return out; }

/*
 <url:https://yukicoder.me/problems/no/127>
 問題文============================================================
 =================================================================
 解説=============================================================
 ================================================================
 */

int N;
int A[3000];

ll dp[2][3000][3000]; // 0 : (l,r]
ll recmax(int dir,int l,int r){
    ll& ret = dp[dir][l][r];
    if(~ret) return ret;
    ret = 1;
    
    if(dir == 0){
        int a = A[l];
        for(int m = l+1; m <= r; m++){
            if(a < A[m]){
                ret = max(ret,recmax(1,l+1,m)+1);
            }
        }
    }else{
        int a = A[r];
        for(int m = l; m < r;m++){
            if(a < A[m]){
                ret = max(ret,recmax(0,m,r-1)+1);
            }
        }
    }
    return ret;
}
ll solve(){
    ll res = 1;
    cin >> N;
    for(int i = 0; i < N;i++) cin >> A[i];
    
    fill(**dp,**dp+2*3000*3000,-1);
    for(int i = 0; i < N;i++){
        res = max(res,recmax(0,i,N-1));
        res = max(res,recmax(1,0,i));
    }
    
    // ===
    for(int i = 0; i < N;i++) A[i] = -A[i];
    fill(**dp,**dp+2*3000*3000,-1);
    for(int i = 0; i < N;i++){
        res = max(res,recmax(0,i,N-1));
        res = max(res,recmax(1,0,i));
    }
    
    
    return res;
}
int main(void) {
    cin.tie(0); ios_base::sync_with_stdio(false);
    cout << solve() << endl;
    return 0;
}