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#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define all(x) (x).begin(), (x).end()
#define f(i, n) for (int i = 0; i < n; i++)
#define trace(x) cerr << #x << ": " << x << '\n'
int n;
const int N = 2e5 + 7;
int arr[N], dp[N];
struct ST
{
    int t[4 * N];
    static const int inf = 1e9;
    ST()
    {
        memset(t, 0, sizeof t);
    }
    void build(int n, int b, int e)
    {
        if (b == e)
        {
            t[n] = 1;
            return;
        }
        int mid = (b + e) >> 1, l = n << 1, r = l | 1;
        build(l, b, mid);
        build(r, mid + 1, e);
        t[n] = max(t[l], t[r]);
    }
    void upd(int n, int b, int e, int i, int x)
    {
        if (b > i || e < i)
            return;
        if (b == e && b == i)
        {
            t[n] = max(t[n], x);
            return;
        }
        int mid = (b + e) >> 1, l = n << 1, r = l | 1;
        upd(l, b, mid, i, x);
        upd(r, mid + 1, e, i, x);
        t[n] = max(t[l], t[r]);
    }
    int query(int n, int b, int e, int i, int j)
    {
        if (b > j || e < i)
            return -inf;
        if (b >= i && e <= j)
            return t[n];
        int mid = (b + e) >> 1, l = n << 1, r = l | 1;
        int L = query(l, b, mid, i, j);
        int R = query(r, mid + 1, e, i, j);
        return max(L, R);
    }
} t;
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cin >> n;
    f(i, N) dp[i] = 1;
    map<int, int> m;
    set<int> st;
    for (int i = 1; i <= n; i++)
        cin >> arr[i], st.insert(arr[i]);
    int i = 1;
    for (auto a : st)
    {
        m[a] = i++;
    }
    for (int i = 1; i <= n; i++)
        arr[i] = m[arr[i]];
    t.build(1, 1, n);
    for (int i = 1; i <= n; i++)
    {
        // for (int j = 1; j < i; j++)
        // {
        //     if (arr[j] < arr[i])
        //         dp[i] = max(dp[i], dp[j] + 1);
        // }
        if (arr[i] != 1)
        {
            int mx = t.query(1, 1, n, 1, arr[i] - 1);
            dp[i] = max(dp[i], mx + 1);
        }
        t.upd(1, 1, N, arr[i], dp[i]);
    }
    int mx = 0;
    for (int i = 1; i <= n; i++)
        mx = max(mx, dp[i]);
    cout << mx << '\n';
}
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