#include <bits/stdc++.h>
#define pb push_back
#define SS ios_base::sync_with_stdio(0);cin.tie(nullptr);cout.tie(nullptr);
#define int long long
#define all(v) v.begin(),v.end()
using namespace std;
const int N = 2e5 + 1, inf = 1e9 + 1, mod = 998244353;
int t[4 * N], add[4 * N];
void push(int v, int tl, int tr){
t[v] = max(0ll, t[v] + add[v]);
if(tl < tr){
add[v * 2] += add[v];
add[v * 2 + 1] += add[v];
}
add[v] = 0;
}
void upd(int v, int tl, int tr, int l, int r, int x){
if(tl > r || l > tr) return;
if(tl >= l && r >= tr){
add[v] += x;
push(v, tl, tr);
return;
}
int mid = (tl + tr) / 2;
upd(v * 2, tl, mid, l, r, x);
upd(v * 2 + 1, mid + 1, tr, l, r, x);
t[v] = t[v * 2] + t[v * 2 + 1];
}
int get(int v, int tl, int tr, int l, int r){
push(v, tl, tr);
if(tl > r || l > tr) return 0ll;
if(tl >= l && r >= tr) return t[v];
int mid = (tl + tr) / 2;
return get(v * 2, tl, mid, l, r) + get(v * 2 + 1, mid + 1, tr, l, r);
}
void solve(){
int n;
cin >> n;
int y[n + 1];
pair<int, int> x[n + 1];
for(int i = 1; i <= n; i++){
cin >> x[i].first;
x[i].second = i;
}
for(int i = 1; i <= n; i++){
cin >> y[i];
upd(1, 1, n, i, i, y[i]);
}
sort(x + 1, x + n + 1);
reverse(x + 1, x + n + 1);
int p[n + 1];
for(int i = 1; i <= n; i++) p[x[i].second] = i;
int ans = 0;
for(int i = 1; i <= n; i++){
int it = x[i].second;
int l = it + 1, r = n;
int res = 0;
while(l <= r){
int mid = (l + r) / 2;
if(get(1, 1, n, mid, it - 1) >= x[i].first){
r = mid - 1;
}
else{
res = mid;
l = mid + 1;
}
}
if(res){
int sum = get(1, 1, n, it + 1, res);
ans += sum;
upd(1, 1, n, it + 1, res, -x[i].first);
x[i].first -= sum;
res++;
if(res > n) continue;
sum = get(1, 1, n, res, res);
ans += min(sum, x[i].first);
upd(1, 1, n, res, res, -x[i].first);
x[i].first -= sum;
}
}
for(int i = 1; i <= n; i++) y[i] = get(1, 1, n, i, i);
for(int i = 1; i <= n; i++){
if(y[i]){
int inc = min(y[i], x[p[i]].first);
y[i] -= inc;
x[p[i]].first -= inc;
}
ans -= y[i];
}
cout << ans;
}
signed main(){
SS
// freopen("trains.in", "r", stdin);
// freopen("trains.out", "w", stdout);
int t = 1;
// cin >> t;
while(t--){
solve();
}
}
