#include <bits/stdc++.h>

using namespace std;

ifstream f("subsir2.in");
ofstream g("subsir2.out");

long long n,i,lungime,maxi,j,ok,indice,maxim,sol[5010],l[5010],v[5010];

int main()
{
    f>>n;
    for(i=1;i<=n;i++)
    {
        f>>v[i];
    }

    l[n]=1;
    for(i=n-1;i>=1;i--)
    {
        maxim=0;
        for(j=i+1;j<=n;j++)
            if(v[j]>=v[i] && l[j]>maxim)maxim=l[j];

        l[i]=maxim+1;
        if(l[i]>maxi)maxi=l[i];
    }

    indice=0;
    lungime=maxi;
    ok=1;


    g<<maxi<<'\n';



    return 0;
}