import java.util.*;
class Pair{
    int num;//大小
    int len;//长度
    public Pair(int num,int len){
        this.num = num;
        this.len = len;
    }
}
public class Main{
    static Pair[] pairs = new Pair[100010];
    public static void main(String[] args){
        Scanner scan = new Scanner(System.in);
        int n = scan.nextInt();
        for(int i=1;i<=n;i++) pairs[i] = new Pair(scan.nextInt(),1);
        for(int i=2;i<=n;i++){
            Arrays.sort(pairs,1,i,new Comparator<Pair>(){
                @Override 
                public int compare(Pair o1,Pair o2){
                    return Integer.compare(o1.num,o2.num);
                }
            });
            //得到第一个比第i个数大或者等于的数的索引
            int index = get(pairs,1,i-1,pairs[i].num);
            //可能全是大于等于第i个数的索引
            if(index==i-1&&pairs[index].num<pairs[i].num){
                index++;
            }
            //如果index为1说明没有比第i个数大或者等于的数的索引
            if(index==1) continue;
                Arrays.sort(pairs,1,index,new Comparator<Pair>(){
                @Override 
                public int compare(Pair o1,Pair o2){
                    return Integer.compare(o1.len,o2.len);
                }
            });
            pairs[i].len = pairs[index-1].len+1;
        }
        int len_max = -1;
        for(int i=1;i<=n;i++)
            if(pairs[i].len>len_max) len_max = pairs[i].len;
        System.out.print(len_max);
    }
    static int get(Pair[] a,int left,int right,int x){
        while(left<right){
            int mid = (left+right)>>1;
            if(a[mid].num>=x) right = mid;
            else left = mid+1;
        }
        return left;
    }
}