#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<ll> vl;
typedef pair<ll, ll> pll;
const ll INF = 1e18;
enum Op { NONE, SET, ADD };
struct Tag { Op op = NONE; ll v = 0; };
struct Seg {
int n;
vl t;
vector<Tag> lz;
Seg(int sz) {
n = sz;
t.resize(4*n);
lz.resize(4*n);
}
private:
void apply(int id, Tag q) {
if (q.op == SET) {
lz[id] = q;
t[id] = q.v;
}
if (q.op == ADD) {
if (lz[id].op != SET) lz[id].op = ADD;
lz[id].v += q.v;
t[id] += q.v;
}
}
void push_down(int id) {
if (lz[id].op == NONE) return;
apply(id*2, lz[id]);
apply(id*2+1, lz[id]);
lz[id] = Tag();
}
void update(int id, int l, int r, int ql, int qr, Tag q) {
if (l >= qr || r <= ql) return;
if (ql <= l && r <= qr) apply(id, q);
else {
push_down(id);
int m = (l+r)/2;
update(id*2, l, m, ql, qr, q);
update(id*2+1, m, r, ql, qr, q);
t[id] = min(t[id*2], t[id*2+1]);
}
}
ll query(int id, int l, int r, int ql, int qr) {
if (l >= qr || r <= ql) return INF;
if (ql <= l && r <= qr) return t[id];
push_down(id);
int m = (l+r)/2;
return min(query(id*2, l, m, ql, qr), query(id*2+1, m, r, ql, qr));
}
public:
void update(int l, int r, Tag q) {
update(1, 0, n, l, r, q);
}
ll query(int l, int r) {
return query(1, 0, n, l, r);
}
};
int main() {
ll n; cin >> n;
vl a(n), b(n);
for (int i = 0; i < n; i++) cin >> a[i];
for (int i = 0; i < n; i++) cin >> b[i];
Seg seg(n);
for (int i = 0; i < n; i++) seg.update(i+1, n, Tag{ADD, b[i]}), seg.update(i, i+1, Tag{ADD, -a[i]});
ll ans = max(ans, seg.query(0, n));
ll all = accumulate(b.begin(), b.end(), 0ll);
for (int i = 1; i < n; i++) {
seg.update(i, n, Tag{ADD, -b[i-1]});
seg.update(0, i-1, Tag{ADD, -b[i-1]});
seg.update(i-1, i, Tag{SET, all-a[i-1]-b[i-1]});
ans = max(ans, seg.query(0, n));
}
cout << max(-ans, 0ll) << endl;
}
