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#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define st first
#define nd second
#define pii pair<ll,ll>
#define pb push_back
#define pf push_front
#define lll __int128
#define si size()
#define int ll
const int A=1e6+3;
int T[A];
int il[A];
signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int sum=0,n,k;
    string a,b,c;
    set<int>s;
    cin>>n;
    vector<int>inp(n+2);
    for(int i=1;i<=n;i++) cin>>inp[i];
    vector<int>v;
    for(int i=n;i>=1;i--){
        while(v.si&&v.back()<=inp[i])
            v.pop_back();
        v.pb(inp[i]);
        T[i]=v.si;
        s.insert(inp[i]);
        il[inp[i]]++;
    }
    int maxi=0,in=1e6;
    v.clear();
    for(int i=1;i<n;i++){
        while(in>=0&&il[in]==0) in--;
        auto it=upper_bound(v.begin(),v.end(),in);
        maxi=max(maxi,T[i]+(v.end()-it));
        il[inp[i]]--;
        if(v.empty()||v.back()<inp[i]) v.pb(inp[i]);       
    }
    cout<<maxi<<'\n';
    return 0; 
}