#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> p32;
typedef pair<ll,ll> p64;
typedef pair<double,double> pdd;
typedef vector<ll> v64;
typedef vector<int> v32;
typedef vector<vector<int> > vv32;
typedef vector<vector<ll> > vv64;
typedef vector<vector<p64> > vvp64;
typedef vector<p64> vp64;
typedef vector<p32> vp32;
ll MOD = 998244353;
double eps = 1e-12;
#define forn(i,e) for(ll i = 0; i < e; i++)
#define forsn(i,s,e) for(ll i = s; i < e; i++)
#define rforn(i,s) for(ll i = s; i >= 0; i--)
#define rforsn(i,s,e) for(ll i = s; i >= e; i--)
#define ln "\n"
#define dbg(x) cout<<#x<<" = "<<x<<ln
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define INF 2e18
#define all(x) (x).begin(), (x).end()
#define sz(x) ((ll)(x).size())
int main()
{
//ifstream cin("in.txt");
int n;
cin >> n;
vector<int> lim(n + 1);
for(int i = 1; i <= n; i++){
cin >> lim[i];
}
vector<int> amount(n + 1);
for(int i = 1; i <= n; i++){
cin >> amount[i];
}
vector<pair<int, int>> a(n + 1);
//f = lim
//s = amount
for(int i = 1; i <= n; i++){
a[i].first = lim[i];
a[i].second = amount[i];
}
sort(a.begin(), a.end());
long long tp = 0;
int l = 1;
int r = n;
long long ans = 0;
while(l <= r){
while(tp != a[l].first){
if(a[r].second < a[l].first - tp){
tp += a[r].second;
ans += 2 * a[r].second;
r--;
}
else{
long long x = a[l].first - tp;
tp += x;
ans += 2 * x;
a[r].second -= x;
}
}
while(l <= r && tp >= a[l].first){
tp += a[l].second;
ans += a[l].second;
l++;
}
/*
if(tp >= a[l].first){
ans++;
a[l].second--;
if(a[l].second == 0){
l++;
}
}
else{
ans += 2;
a[r].second--;
if(a[r].second == 0){
r--;
}
}
tp++;*/
}
cout << ans;
//ha valamit tudsz 1 perc alatt akkor szedd azt
//ha nem akkor szedd azt aminek a legnagyobb az lim-je?
/*
3 - 1 X
4 - 5 -> 3
5 - 1 X
tp: 1 + 1 + 1 + 1
ans: 2 + 2 + 2 + 1 + 1 + 1 + 1
*/
}