#include <bits/stdc++.h>
#define REP(i,a,b) for (auto i = (a); i <= (b); ++i)
#define PER(i,a,b) for (auto i = (b); i >= (a); --i)
#define log2(x) (31-__builtin_clz(x))
#define ALL(x) (x).begin(), (x).end()
#define RALL(x) (x).rbegin(), (x).rend()
#define SZ(x) (int)(x).size()
#define PB push_back
#define FI first
#define SE second
#define mup(x,y) x = min(x,y)
#define Mup(x,y) x = max(x,y)
#define debug(x) cout << #x << " is " << x << el
#define el '\n'
using namespace std; using ll = long long; using ii = pair<int,int>; using iii = tuple<int,int,int>;
void solution(); int main() {ios::sync_with_stdio(0); cin.tie(0); solution();}
const int N = 100003; const ll MOD = 1e9+7;
int n; ll h[N], w[N], prefix[N];
inline ll bin2(ll x) {return (x*(x-1)/2)%MOD;}
int tree[N<<2];
void update(int t, int x, iii node = {1,1,n}) {
auto [k,l,r] = node;
if (t < l || r < t) return;
if (l == r) {tree[k] = x; return;}
int m = (l+r)>>1;
update(t,x,{k<<1,l,m}); update(t,x,{(k<<1)|1,m+1,r});
tree[k] = min(tree[k<<1], tree[(k<<1)|1]);
}
auto query(ii range, iii node = {1,1,n}) {
auto [s,e] = range; auto [k,l,r] = node;
if (e < l || r < s) return tree[0];
if (s <= l && r <= e) return tree[k];
int m = (l+r)>>1;
return min(query(range,{k<<1,l,m}), query(range,{(k<<1)|1,m+1,r}));
}
bool input() {
cin >> n;
fill(tree,tree+(N<<2),1000000003);
cin >> h[1]; update(1,h[1]);
int v = h[1]; bool allsame = true;
REP(i,2,n) {
cin >> h[i];
if (h[i] != v) allsame = false;
update(i,h[i]);
}
REP(i,1,n) {cin >> w[i]; prefix[i] = (prefix[i-1]+w[i])%MOD;}
return allsame;
}
void task1() {
ll ans = 0;
REP(i,1,n) {
ans += (bin2(h[i]+1)*bin2(w[i]+1))%MOD;
ans %= MOD;
}
REP(i,1,n) REP(j,i+1,n) {
ans += (bin2(query({i,j})+1)*((w[i]*w[j])%MOD))%MOD;
ans %= MOD;
}
cout << ans;
} void task2() {
cout << (bin2(h[1]+1)*bin2(prefix[n]+1))%MOD;
}
void solution() {
if (input()) task2();
else task1();
}
