#include <iostream>
#include <algorithm> // for sort, mainly
#include <vector>
#include <map>
#include <set>
#include <cmath>
#include <array>
#include <string>
#include <cstdio>
#include <iterator>
#include <unordered_set>
#include <cstdint> // for int64_t, int32_t, etc
#include <queue>
#include <stack>
#include <deque>
#include <numeric> // gcd, lcm
#include <fstream>
#include <bitset> // for bitset
#include <iomanip>
#include <cassert> // for set with custom ordering
#include <type_traits> // for set with custom ordering
#include <utility> // for swap, forward, etc
using namespace std;

#pragma GCC optimize("O2")
// #pragma GCC optimize("O1","O2","O3","Ofast","unroll-loops")
// #pragma GCC target("sse","sse2","sse3","sse4.1","sse4.2","avx","avx2","fma")

template<typename A, typename B> ostream& operator<<(ostream &os, const pair<A, B> &p) { return os << '(' << p.first << ", " << p.second << ')'; }
template<typename T_container, typename T = typename enable_if<!is_same<T_container, string>::value, typename T_container::value_type>::type> ostream& operator<<(ostream &os, const T_container &v) { os << '{'; string sep; for (const T &x : v) os << sep << x, sep = ", "; return os << '}'; }
void dbg_out() { cout << endl; }
template<typename Head, typename... Tail> void dbg_out(Head H, Tail... T) { cout << ' ' << H; dbg_out(T...); }
#ifdef LOCAL
#define dbg(...) cout << "(" << #__VA_ARGS__ << "):", dbg_out(__VA_ARGS__)
#else
#define dbg(...)
#endif

/*

notes:

int64_t
stoi(string s) -> string to int
to_string() -> int (or else) to string

vector declaration:
vector<ll> v(n, 0)
vector<vector<ll>> v(n, vector<ll>(n, 0));

{if statement} ? {truth value} : {false value}

#ifdef LOCAL
    freopen("in.txt","r",stdin);
    freopen("out.txt","w",stdout);
#endif

std::lcm(ll a, ll b), std::gcd(int a, int b)

cout << fixed << setprecision(n);

set with custom ordering
set<ll, decltype(&cmp)> qu(cmp);

*/

typedef int64_t ll;

void solve() {

	ll n;
	cin >> n;
	vector<pair<ll,ll>> v(n, {0,0}); 
	vector<pair<ll,ll>> minexp(n, {0,0}); // minimum experience, index
	vector<pair<ll,ll>> amount(n, {0,0}); // amount, index
	for(ll i = 0; i < n; i++) {
		cin >> v[i].first;
		minexp[i] = {v[i].first, i};
	}
	for(ll i = 0; i < n; i++) {
		cin >> v[i].second;
		amount[i] = {v[i].second, i};
	}

	sort(minexp.begin(), minexp.end());
	sort(amount.begin(), amount.end());

	ll ex = 0;
	ll ans = 0;

	ll i = 0, j = n - 1;
	// i is the iterator for minexp
	// j is the iterator for amount

	ll proc = 0;
	while(proc < n) {

		ll left = minexp[i].second;
		ll right = amount[j].second;

		//cerr << "\ni=" << i << "; j=" << j;
		//cerr << "\nleft=" << left << "; right=" << right;

		//cerr << "\nv=" << v;
		//cerr << "\nex=" << ex << "; ans=" << ans << "; proc=" << proc;

		if(left == right) {
			
			// na ennyi volt
			// jol ment fiuk, nincs mar honnan csorni

			for(ll k = i; k < n; k++) {

				ll curr = minexp[k].second;

				ll cex = v[curr].first;
				ll cam = v[curr].second;

				if(cam == 0) {
					continue;
				}

				if(cex <= ex) {
					ans += cam;
					ex += cam;
				}else{

					ll till = cex - ex;
					if(till >= cam) {

						ans += 2 * cam;
						ex += cam;

					}else{

						ans += 2 * till;
						ll yet = cam - till;
						ans += yet;
						ex += cam;

					}

				}

				proc++;

			}

			break;

		}else{

			ll lex = v[left].first;	
			ll lam = v[left].second;

			ll rex = v[right].first;
			ll rem = v[right].second;

			if(rem == 0) {
				j--;
				continue;
			}

			if(lex <= ex) {

				ex += lam;
				ans += lam;

				v[left].second = 0;
				i++;
				proc++;
			}else{

				ll diff = lex - ex;
				
				if(diff < rem) {

					v[right].second -= diff;
					ans += 2 * diff;
					ex += diff;

				}else{

					// rem <= diff

					v[right].second = 0;
					ans += 2 * rem;
					ex += rem;
					proc++;
					j--;

				}

			}

		}

	}
	

	cout << ans;

}

int main()
{
	std::ios_base::sync_with_stdio(false);
	//cin.tie(nullptr);
	//cout.tie(nullptr);

	solve();

	return 0;
}