#include using namespace std; //* #include using namespace atcoder; //using mint = modint998244353; using mint = modint1000000007; //using mint = modint; //*/ using ll = long long; using ld = long double; using pll = pair; using tlll = tuple; constexpr ll INF = 1LL << 60; template bool chmin(T& a, T b) {if (a > b) {a = b; return true;} return false;} template bool chmax(T& a, T b) {if (a < b) {a = b; return true;} return false;} ll safemod(ll A, ll M) {ll res = A % M; if (res < 0) res += M; return res;} ll divfloor(ll A, ll B) {if (B < 0) {return divfloor(-A, -B);} return (A - safemod(A, B)) / B;} ll divceil(ll A, ll B) {if (B < 0) {return divceil(-A, -B);} return divfloor(A + B - 1, B);} ll pow_ll(ll A, ll B) {ll res = 1; for (int i = 0; i < B; i++) {res *= A;} return res;} ll arisum_ll(ll a, ll d, ll n) { return n * a + (n & 1 ? ((n - 1) >> 1) * n : (n >> 1) * (n - 1)) * d; } ll arisum2_ll(ll a, ll l, ll n) { return n & 1 ? ((a + l) >> 1) * n : (n >> 1) * (a + l); } ll arisum3_ll(ll a, ll l, ll d) { assert((l - a) % d == 0); return arisum2_ll(a, l, (l - a) / d + 1); } template void unique(vector &V) {V.erase(unique(V.begin(), V.end()), V.end());} template void sortunique(vector &V) {sort(V.begin(), V.end()); V.erase(unique(V.begin(), V.end()), V.end());} #define FINALANS(A) do {cout << (A) << '\n'; exit(0);} while (false) template void printvec(const vector &V) {int _n = V.size(); for (int i = 0; i < _n; i++) cout << V[i] << (i == _n - 1 ? "" : " ");cout << '\n';} template void printvect(const vector &V) {for (auto v : V) cout << v << '\n';} template void printvec2(const vector> &V) {for (auto &v : V) printvec(v);} int main() { ll N; cin >> N; vector A(N), B(N); for (ll i = 0; i < N; i++) { cin >> A.at(i); } for (ll i = 0; i < N; i++) { cin >> B.at(i); } vector ord(N); for (ll i = 0; i < N; i++) { ord.at(i) = i; } sort(ord.begin(), ord.end(), [&](ll i, ll j) { return A.at(i) * (1 - B.at(j)) > A.at(j) * (1 - B.at(i)); }); mint ans = 0, x = 1; for (auto i : ord) { ans += A.at(i) * x; x *= B.at(i); } cout << ans.val() << endl; }