#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;
int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	int n;
	cin >> n;
	vector<pair<int, int>> anyag(n);
	for (int i = 0; i < n; i++)
	{
		cin >> anyag[i].second;
	}
	for (int i = 0; i < n; i++)
	{
		cin >> anyag[i].first;
	}
	sort(anyag.begin(), anyag.end(), [](auto s1, auto s2) {
		return s1.second < s2.second;
		});
	int i = 0;
	int j = n - 1;
	long long ido = 0;
	long long exp = 0;
	while (i <= j)
	{
		while (i <= j and exp >= anyag[i].second)
		{
			exp += anyag[i].first;
			ido += anyag[i].first;
			i++;
		}
		if (i > j) break;
		long long kell = anyag[i].second - exp;
		if (kell >= anyag[j].first)
		{
			exp += anyag[j].first;
			ido += 2 * anyag[j].first;
			j--;
		}
		else
		{
			exp += kell;
			ido += 2 * kell;
			anyag[j].first -= kell;
		}
	}
	cout << ido;
}