#include <iostream>
#include <algorithm>
#include <utility>
#include <string>
#include <vector>
#include <set>
#include <stack>
#include <queue>
#include <map>
#include <math.h>
#include <string.h>
#include <iomanip>
#include <numeric>
#include <cstdlib>
#include <cstdint>
#include <cmath>
#include <functional>
#include <limits>
#include <cassert>

using namespace std;

/* template */

using ll = long long;

void debug_out() { std::cout << std::endl; }
 
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
  cout << H << " ";
  debug_out(T...);
}

#ifdef LOCAL
#define debug(...) cout << "debug: "; debug_out(__VA_ARGS__)
#else
#define debug(...) 
#endif

#define rep(i, a, n) for (int i = (int)(a); i < (int)(n); i++)
#define rrep(i, a, n) for (int i = ((int)(n-1)); i >= (int)(a); i--)
#define Rep(i, a, n) for (long long i = (long long)(a); i< (long long)(n); i++)
#define RRep(i, a, n) for (long long i = ((long long)(n-1ll)); i>=(long long)(a); i--)
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()

template <typename T>
std::ostream& operator<<(std::ostream& os, std::vector<T> vec) {
  for (std::size_t i = 0; i < vec.size(); i++)os << vec[i] << (i + 1 == vec.size() ? "" : " ");
  return os;
}

struct Edge{
    int to;
    ll weight;
    Edge(int t, ll w) : to(t), weight(w){ }
};

struct edge{
    int from;
    int to;
    ll weight;
    edge(int f,int t,ll w) : from(f), to(t), weight(w){ }
};


using Graph = vector<vector<Edge>>;
using graph = vector<vector<int>>;
using edges = vector<edge>;

template <class T>
inline bool chmin(T &a, T b){
    if (a > b){
        a = b;
        return true;
    }
    return false;
}

template <class T>
inline bool chmax(T &a, T b){
    if (a < b){
        a = b;
        return true;
    }
    return false;
}

template <class T>
T lcm(T a, T b){
    return (a*b)/gcd(a,b);
}

bool isPalindrome(string s){
    string t = s;
    reverse(all(t));
    return s==t;
}

constexpr ll LNF = __LONG_LONG_MAX__;

constexpr int INF = 1e9+7;

const double PI=3.14159265358979323846;


vector<int> dx = {-1,0,1,0,-1,1,-1,1};
vector<int> dy = {0,-1,0,1,1,-1,-1,1};

/* template */

template<class T>
struct SegmentTree{
    private:
      using F=std::function<T(T,T)>;

      T n;
      T ide_ele;
      std::vector<T> seg;
      F fn;
    
    public:
      //要素数_n,単位元ide_ele,比較関数funで初期化
      SegmentTree(T _n,T ide_ele,F fun) : ide_ele(ide_ele), fn(fun){
          n = 1;
          while(n<_n) n *= 2;
          seg.assign(2*n-1,ide_ele);
      }

      //配列ide_val,単位元ide_val,比較関数funで初期化
      SegmentTree(std::vector<T> &ide_val,T ide_ele,F fun): ide_ele(ide_ele), fn(fun){
          n = 1;
          T _n = ide_val.size();
          while(n<_n) n *=2;
          seg.assign(2*n-1, ide_ele);
          for(T i = 0; i<_n; i++) seg[n+i-1] = ide_val[i];
          for(T i = n-2; i>=0; i++) seg[i] = fn(seg[2*i+1],seg[2*i+2]);
      }

      void update(T index,T x,bool flag=false){
          T k = index+n-1;
          if(flag) seg[k] +=x;
          else seg[k] = x;
          while(k>0){
              k = (k-1)/2;
              seg[k] = fn(seg[2*k+1],seg[2*k+2]);
          }
      }

      //[a,b)の区間でquery処理
      T query(T a,T b){
          if(a<0 || n<b) return ide_ele;
          T lval = ide_ele, rval = ide_ele;
          T l = a+n-1, r = b+n-1;
          for(;l<r;l=(l>>1),r=(r>>1)){
              if(!(r&1)){
                  r--;
                  rval = fn(seg[r],rval);
              }
              if(!(l&1)){
                  lval = fn(lval,seg[l]);
                  l++;
              }
          }
          return fn(lval,rval);
      }
};

int main(){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    int n; cin >> n;
    vector<ll> h(n),a(n);
    rep(i,0,n){
        cin >> h[i];
        h[i]--;
    }
    rep(i,0,n) cin >> a[i];
    SegmentTree<ll> seg(n,0,[](ll a,ll b){ return max(a,b); });
    rep(i,0,n){
        ll x = seg.query(0,h[i]);
        seg.update(h[i],x+a[i]);
    }
    cout << seg.query(0,n) << endl;
}

Measured memory_bytes: 7552