#include <iostream>
#include <fstream>
#include <iomanip>
#include <climits>
#include <limits>
#include <algorithm>
#include <array>
#include <vector>
#include <deque>
#include <queue>
#include <list>
#include <stack>
#include <string>
#include <functional>
#include <numeric>
#include <map>
#include <set>
#include <cstdlib>
#include <bitset>
#include <unordered_map>
#include <random>
#include <cmath>
#include <complex>
// #include "utiltime.hpp"

using namespace std;

typedef long long int ll;
typedef vector<int> vi;
typedef vector<vector<int>> vvi;
typedef pair<int, int> P;
typedef pair<ll, ll> Pll;
typedef vector<ll> vll;
typedef vector<vector<ll>> vvll;
typedef complex<double> cdouble;

const int INFL = (int)1e9;
const ll INFLL = (ll)1e18;
const double INFD = numeric_limits<double>::infinity();
const double PI = 3.14159265358979323846;
#define Loop(i, n) for(int i = 0; i < (int)(n); i++)
#define Loopll(i, n) for(ll i = 0; i < (ll)(n); i++)
#define Loop1(i, n) for(int i = 1; i <= (int)(n); i++)
#define Loopll1(i, n) for(ll i = 1; i <= (ll)(n); i++)
#define Loopr(i, n) for(int i = (int)(n) - 1; i >= 0; i--)
#define Looprll(i, n) for(ll i = (ll)(n) - 1; i >= 0; i--)
#define Loopr1(i, n) for(int i = (int)(n); i >= 1; i--)
#define Looprll1(i, n) for(ll i = (ll)(n); i >= 1; i--)
#define Foreach(buf, container) for(auto buf : container)
#define Loopdiag(i, j, h, w, sum) for(int i = ((sum) >= (h) ? (h) - 1 : (sum)), j = (sum) - i; i >= 0 && j < (w); i--, j++)
#define Loopdiagr(i, j, h, w, sum) for(int j = ((sum) >= (w) ? (w) - 1 : (sum)), i = (sum) - j; j >= 0 && i < (h); j--, i++)
#define Loopdiagsym(i, j, h, w, gap) for (int i = ((gap) >= 0 ? (gap) : 0), j = i - (gap); i < (h) && j < (w); i++, j++)
#define Loopdiagsymr(i, j, h, w, gap) for (int i = ((gap) > (h) - (w) - 1 ? (h) - 1 : (w) - 1 + (gap)), j = i - (gap); i >= 0 && j >= 0; i--, j--)
#define Loopitr(itr, container) for(auto itr = container.begin(); itr != container.end(); itr++)
#define printv(vector) Loop(extra_i, vector.size()) { cout << vector[extra_i] << " "; } cout << endl;
#define printmx(matrix) Loop(extra_i, matrix.size()) { Loop(extra_j, matrix[extra_i].size()) { cout << matrix[extra_i][extra_j] << " "; } cout << endl; }
#define quickio() ios::sync_with_stdio(false); cin.tie(0);
#define readfile(filename) ifstream in(filename); cin.rdbuf(in.rdbuf());
#define bitmanip(m,val) static_cast<bitset<(int)m>>(val)
bool nearlyeq(double x, double y) { return abs(x - y) < 1e-9; }
bool inrange(int x, int t) { return x >= 0 && x < t; }
ll rndf(double x) { return (ll)(x + (x >= 0 ? 0.5 : -0.5)); }
ll floorsqrt(double x) { ll m = (ll)sqrt(x); return m + (m * m <= (ll)(x) ? 0 : -1); }
ll ceilsqrt(double x) { ll m = (ll)sqrt(x); return m + ((ll)x <= m * m ? 0 : 1); }
ll rnddiv(ll a, ll b) { return (a / b + (a % b * 2 >= b ? 1 : 0)); }
ll ceildiv(ll a, ll b) { return (a / b + (a % b == 0 ? 0 : 1)); }
ll gcd(ll m, ll n) { if (n == 0) return m; else return gcd(n, m % n); }

/*******************************************************/

typedef ll seg_t;

class SegTree {
private:
	int n;
	vector<seg_t> segs;
	int left_of(int index) {
		return index * 2 + 1;
	}
	int right_of(int index) {
		return index * 2 + 2;
	}
	void local_update(int index, seg_t(*update_rule)(seg_t, seg_t)) {
		int l = left_of(index), r = index * 2 + 2;
		segs[index] = update_rule(segs[l], segs[r]);
	}
	void get_index_of_range_rec(int s, int t, int l, int r, int index, vi *v) {
		if (s == l && t == r) v->push_back(index);
		else {
			int mid = (l + r) / 2;
			if (s < mid && mid < t) {
				get_index_of_range_rec(s, mid, l, mid, left_of(index), v);
				get_index_of_range_rec(mid, t, mid, r, right_of(index), v);
			}
			else if (s < mid) {
				get_index_of_range_rec(s, t, l, mid, left_of(index), v);
			}
			else if (mid < t) {
				get_index_of_range_rec(s, t, mid, r, right_of(index), v);
			}
		}
	}
public:
	SegTree(vector<seg_t> a, seg_t init, seg_t(*update_rule)(seg_t, seg_t)) {
		n = (int)pow(2, ceil(log2(a.size())));
		segs = vector<seg_t>(n * 2 - 1, init);
		Loop(i, a.size()) segs[n - 1 + i] = a[i];
		Loopr(i, n - 1) local_update(i, update_rule);
	}
	void update(int k, seg_t x, seg_t(*update_rule)(seg_t, seg_t), bool add_flag = false) {
		int index = k + n - 1;
		segs[index] = add_flag ? segs[index] + x : x;
		while (index > 0) {
			index = (index - 1) / 2;
			local_update(index, update_rule);
		}
	}
	// note: range [s, t)
	vi get_index_of_range(int s, int t) {
		vi ret = {};
		get_index_of_range_rec(s, t, 0, n, 0, &ret);
		return ret;
	}
	// note: indices.size() should not be 0, indices should not be intersected
	seg_t independent_combine(vi indices, seg_t(*update_rule)(seg_t, seg_t)) {
		seg_t ret = segs[indices.back()];
		Loopr(i, indices.size() - 1) {
			ret = update_rule(segs[indices[i]], ret);
		}
		return ret;
	}
	// write extend method from here:
	seg_t max_of_range(int s, int t) {
		vi v = get_index_of_range(s, t);
		seg_t ret = 0;
		Loop(i, v.size()) {
			ret = max(ret, segs[v[i]]);
		}
		return ret;
	}
};

seg_t update_rule(seg_t a, seg_t b) {
	return max(a, b);
}

int main() {
	int n; cin >> n;
	vi h(n);
	Loop(i, n) {
		cin >> h[i];
		h[i]--;
	}
	vll a(n); Loop(i, n) cin >> a[i];
	SegTree segtree(vll(n, 0), 0, update_rule);
	Loop(i, n) {
		ll k = segtree.max_of_range(0, h[i]);
		segtree.update(h[i], k + a[i], update_rule);
	}
	cout << segtree.max_of_range(0, n) << endl;
}

Measured memory_bytes: 8192