#include #include #define rep(i,n) for (int i = 0; i < int(n); ++i) #define repp(i,n,m) for (int i = m; i < int(n); ++i) #define repb(i,n) for (int i = int(n)-1; i >= 0; --i) using namespace std; using namespace atcoder; using ll = long long; using ld = long double; using P = pair; using PL = pair; using pdd = pair; using pil = pair; using pli = pair; using ppi = pair; using pip = pair; const int INF = 1001001007; const long long mod1 = 1000000007LL; const long long mod2 = 998244353LL; const ll inf = 2e18; const ld pi = 3.14159265358979323; const ld eps = 1e-7; templatevoid o(T a); templateistream &operator>>(istream &is,vector &v){for(auto &e:v)is>>e;return is;} templateistream &operator>>(istream &is,vector> &v){for(auto &e:v)is>>e;return is;} templatebool range(T a,T b,T x){return (a<=x&&xbool rrange(T a,T b,T c,T d,T x,T y){return (range(a,c,x)&&range(b,d,y));} templatevoid rev(vector &v){reverse(v.begin(),v.end());} void revs(string &s) {reverse(s.begin(),s.end());} templatevoid sor(vector &v, int f=0){sort(v.begin(),v.end());if(f!=0) rev(v);} templatebool chmin(T &a,const T &b){if(a>b){a=b;return true;}return false;} templatebool chmax(T &a,const T &b){if(avoid uniq(vector &v){sor(v);v.erase(unique(v.begin(),v.end()),v.end());} templateT cel(T a,T b){return (a+b-1)/b;} templatevoid print(pair a); templatevoid print(vector v); templatevoid print(vector> v); void print(){ putchar(' '); } void print(bool a){ printf("%d", a); } void print(int a){ printf("%d", a); } void print(long a){ printf("%ld", a); } void print(long long a){ printf("%lld", a); } void print(char a){ printf("%c", a); } void print(char a[]){ printf("%s", a); } void print(const char a[]){ printf("%s", a); } void print(long double a){ printf("%.15Lf", a); } void print(const string& a){ for(auto&& i : a) print(i); } template void print(const T& a){ cout << a; } int out(){ putchar('\n'); return 0; } template int out(const T& t){ print(t); putchar('\n'); return 0; } template int out(const Head& head, const Tail&... tail){ print(head); putchar(' '); out(tail...); return 0; } void o(){cout<<"!?"<void o(T a){cout<void print(pair a){print(a.first);print(),print(a.second);} templatevoid print(vector v){for(auto ite=v.begin();ite!=v.end();){print(*ite);if(++ite!=v.end())print();}} templatevoid print(vector> v){for(auto ite=v.begin();ite!=v.end();){print(*ite);if(++ite!=v.end())out();}} void yes(){out("Yes");} void no (){out("No");} void yn (bool t){if(t)yes();else no();} templatevoid dame(bool t, T s){if(!t){out(s);exit(0);}} vector dx = {0,1,0,-1,1,1,-1,-1}; vector dy = {1,0,-1,0,1,-1,-1,1}; const string ALP = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; const string alp = "abcdefghijklmnopqrstuvwxyz"; const string NUM = "0123456789"; ll gcd(ll a,ll b){return b?gcd(b,a%b):a;} ll lcm(ll a,ll b){return a/gcd(a,b)*b;} ll mpow(ll x,ll n,ll m){if(n==0)return 1LL;x%=m;ll a=mpow(x,n/2,m);a=a*a%m;return (n&1)?a*x%m:a;} ll op(ll a, ll b){return a + b;} ll e(){return 0;} void solve(){ int n; cin >> n; vector a(n), b(n), idx(n); cin >> a >> b; rep(i,n) idx[i] = i; auto compare = [&](int l, int r){ return a[l] * (1-b[r]) > a[r] * (1-b[l]); }; sort(idx.begin(),idx.end(),compare); using mint = modint1000000007; mint ans = 0; mint ima = 1; rep(i,n){ ans += ima * a[idx[i]]; ima *= b[idx[i]]; } out(ans.val()); } int main(){ int t = 1; //cin >> t; while(t--) solve(); }