#include <bits/stdc++.h>
using namespace std;
int main() {
    int n; cin >> n;
    vector<int> pf(n+1),a(n+1),b(n+1);
    for (int i = 1; i <= n; i++) cin >> a[i];
    for (int i = 1; i <= n; i++) cin >> b[i];
    for (int i = 1; i <= n; i++) pf[i] = pf[i-1]+b[i];
    int l = 1, r = 0, sum = 0, out = 1e9;
    while (l <= n && r <= n) {
        out = min(out,sum+pf[l-1]+pf[n]-pf[r]);
        if (sum <= pf[r]-pf[l-1]) {
            r++;
            if (r <= n) sum += a[r];
        }
        else {
            sum -= a[l];
            l++;
        }
    }
    cout << out;
}