#pragma GCC optimize(2)
#include <bits/stdc++.h>
#define int long long
using namespace std;
int a[1000001], t[1000001], dp[1000001], maxn[1000001], n, ans;
vector<int> tree[1000001];
int lowbit(int x)
{
    return x & (-x);
}
void add(int x, int y)
{
    while (x <= n)
    {
        maxn[x] = max(maxn[x], y);
        x += lowbit(x);
    }
}
int query(int x)
{
    int res = 0;
    while (x)
    {
        res = max(res, maxn[x]);
        x -= lowbit(x);
    }
    return res;
}
signed main()
{
    scanf("%lld", &n);
    for (int i = 1; i <= n; i++)
    {
        scanf("%lld", &t[i]);
    }
    for (int i = 1; i <= n; i++)
    {
        scanf("%lld", &a[i]);
        a[i] *= t[i];
    }
    for (int i = 1; i <= n; i++)
    {
        if (i >= t[i])
            tree[i - t[i]].push_back(i);
        else
            tree[0].push_back(i);
    }
    for (int i = 0; i <= n; i++)
    {
        ans = max(ans, dp[i]);
        if (i != 0)
            add(i + t[i], dp[i]);
        for (int x : tree[i])
            dp[x] = query(x) + a[x];
    }
    printf("%lld", ans);
    return 0;
}