#include <bits/stdc++.h>
using namespace std;
#define int long long
#define stoi stoll
using ll=long long;
using vi=vector<int>;
using pii=pair<int,int>;
#define ALL(c) begin(c),end(c)
#define RALL(c) rbegin(c),rend(c)
#define ITR(i,b,e) for(auto i=(b);i!=(e);++i)
#define FORE(x,c) for(auto &&x:c)
#define REPF(i,a,n) for(int i=a,i##len=(int)(n);i<i##len;++i)
#define REP(i,n) REPF(i,0,n)
#define REPR(i,n) for(int i=(int)(n);i>=0;--i)
#define SZ(c) ((int)c.size())
#define CONTAIN(c,x) (c.find(x)!=end(c))
#define INSEG(l,x,r) ((l)<=(x)&&(x)<(r))
#define dump(...)
#define pb push_back
#define _ 0
const signed INF_=1001001001; const long long INF=1001001001001001001LL;
const int DX[9]={0,1,0,-1,1,1,-1,-1,0},DY[9]={-1,0,1,0,-1,1,1,-1,0};
template<class T> ostream& operator<<(ostream &os,const vector<T> &v) {
    ITR(i,begin(v),end(v))os<<*i<<(i==end(v)-1?"":" ");return os;}
template<class T> istream& operator>>(istream &is,vector<T> &v) {
    ITR(i,begin(v),end(v)) is>>*i;return is;}
template<class T,class U> istream& operator>>(istream &is, pair<T,U> &p) {
    is>>p.first>>p.second;return is;}
template<class T, class U> bool chmax(T &a,const U &b){return a<b?a=b,1:0;}
template<class T, class U> bool chmin(T &a,const U &b){return a>b?a=b,1:0;}
template <class T> void PSUM(T& c) {partial_sum(begin(c), end(c), begin(c));}
template<class T> using heap=priority_queue<T,vector<T>,greater<T>>;
struct before_main_function {
    before_main_function() {
        cin.tie(0); ios::sync_with_stdio(false);
        cout << setprecision(15) << fixed;
        #define endl "\n"
    }
} before_main_function;
//------------------8<------------------------------------8<--------------------

template<typename Monoid>
struct SegmentTree {
    using T = typename Monoid::T;
    size_t n;
    vector<T> t;

    void prop_to(std::size_t i) { t[i] = Monoid::op(t[i << 1], t[i << 1 | 1]); }
    SegmentTree(size_t size, const T& v = Monoid::identity()) {
        n = 1;
        while (n < size) n <<= 1;
        t.resize(n << 1, v);
    }
    template <class InputIt>
    SegmentTree(InputIt first, InputIt last) : n(distance(first, last)), t(n << 1, Monoid::identity()) {
        copy(first, last, begin(t) + n);
        for (size_t i = n - 1; i > 0; i--) prop_to(i);
    }
    static T modify_update(const T& a, const T& b) { return b; }
    static T modify_add(const T& a, const T& b) { return a + b; }
    void update(size_t i, const T& v, const function<T(T, T)>& func = modify_update) {
        i += n;
        t[i] = func(t[i], v);
        while (i >>= 1) prop_to(i);
    }
    T query(size_t l, size_t r) {
        T res = Monoid::identity();
        for (l += n, r += n; l < r; l >>= 1, r >>= 1) {
            if (l & 1) res = Monoid::op(res, t[l++]);
            if (r & 1) res = Monoid::op(res, t[--r]);
        }
        return res;
    }
    T get(size_t i) { return t[i + n]; }
};

struct RMQ {
    using T = int;
    static T op(T a, T b) { return max(a, b); }
    static constexpr T identity() { return 0; }
};

signed main() {
    int N;
    cin >> N;
    vector<int> h(N), a(N);
    cin >> h >> a;
    
    auto h_cmp = h;
    sort(ALL(h_cmp));
    h_cmp.erase(unique(ALL(h_cmp)), end(h_cmp));
    auto get_idx = [&](int x) { return lower_bound(ALL(h_cmp), x) - begin(h_cmp); };

    SegmentTree<RMQ> seg(N + 1);
    REP(i, N) {
        int t = get_idx(h[i]);
        int mx = seg.query(0, t);
        seg.update(t, mx + a[i]);
    }
    cout << seg.query(0, N + 1) << endl;
    return (0^_^0);
}



Measured memory_bytes: 9088