#include <iostream>
using namespace std;

int main() {
    int n; cin >> n;
    long long a[n+1], b[n+1];
    for (int i = 0; i <= n; i++) cin >> a[i];
    for (int i = 0; i <= n; i++) cin >> b[i];
    long long s = 0, ans = 0;
    const long long M = 1000000007;
    for (int i = 0; i <= n; i++) {
        s += b[i];
        if (s >= M) s -= M;
        ans += a[n-i] * s % M;
        if (ans >= M) ans -= M;
    }
    cout << ans << endl;
}