#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll mod = 1e9 + 7;
ll solve_rect(ll h, ll w) {
h %= mod;
w %= mod;
ll hc = (h * (h + 1) / 2) % mod;
ll wc = (w * (w + 1) / 2) % mod;
return (hc * wc) % mod;
}
int main() {
ios::sync_with_stdio(0), cin.tie(0);
int n;
cin >> n;
set<pair<ll, int>, greater<pair<ll, int>>> height_index_set;
map<int, pair<ll, ll>> index_dim_map;
height_index_set.insert({0, -1});
height_index_set.insert({0, n});
index_dim_map[-1] = {0, 0};
index_dim_map[n] = {0, 0};
{
vector<ll> hv(n), wv(n);
for (ll& h : hv) cin >> h;
for (ll& w : wv) cin >> w;
for (int i = 0; i < n; i++) {
if (i != n + 1 && hv[i] == hv[i + 1]) {
wv[i + 1] += wv[i];
continue;
}
index_dim_map[i] = {hv[i], wv[i]};
height_index_set.insert({hv[i], i});
}
}
ll res = 0;
while (height_index_set.size() > 1) {
auto _it = height_index_set.begin();
int ind_curr = _it->second;
height_index_set.erase(_it);
// should always be the iterator at key ind_curr
auto it_curr = index_dim_map.lower_bound(ind_curr);
auto& [h_curr, w_curr] = it_curr->second;
auto it_next = it_curr;
it_next++;
auto& [h_next, w_next] = it_next->second;
auto it_prev = it_curr;
it_prev--;
auto& [h_prev, w_prev] = it_prev->second;
res += solve_rect(h_curr, w_curr);
if (h_prev > h_next) {
res -= solve_rect(h_prev, w_curr);
w_prev = (w_prev + w_curr) % mod;
}
else if (h_prev < h_next) {
res -= solve_rect(h_next, w_curr);
w_next = (w_next + w_curr) % mod;
}
else {
res -= solve_rect(h_prev, w_curr);
w_prev = (w_prev + w_curr + w_next) % mod;
height_index_set.erase({h_next, it_next->first});
index_dim_map.erase(it_next);
}
res = (res % mod + mod) % mod;
index_dim_map.erase(it_curr);
}
cout << res;
}
