#include <bits/stdc++.h>
using namespace std;
const long long MOD = (long long) 1e9 + 7;
class dsu {
private:
vector<int> p, rank;
vector<long long> sz;
public:
dsu(int n, const vector<long long> &_sz) : sz(_sz) {
p.assign(n, -1);
rank.assign(n, 0);
}
int root(int x) {
if (p[x] == -1) {
return x;
}
return (p[x] = root(p[x]));
}
bool same_set(int x, int y) {
return (root(x) == root(y));
}
void connect(int x, int y) {
x = root(x); y = root(y);
if (x != y) {
if (rank[x] > rank[y]) {
p[y] = x;
sz[x] = (sz[y] + sz[x]) % MOD;
} else {
p[x] = y;
sz[y] = (sz[x] + sz[y]) % MOD;
if (rank[x] == rank[y]) {
rank[y]++;
}
}
}
}
long long st_sz(int x) {
return sz[root(x)];
}
};
long long modpow(long long b, long long p) {
if (p == 0) {
return 1;
}
long long ans = modpow((b * b) % MOD, p / 2);
if (p % 2 == 1) {
ans = (ans * b) % MOD;
}
return ans;
}
long long inv(long long x) {
return modpow(x, MOD - 2);
}
long long mul(long long a, long long b) {
return (a * b) % MOD;
}
long long f(long long h, long long w) {
return mul(h, mul(h + 1, mul(w, mul(w + 1, inv(4)))));
}
int main() {
ios::sync_with_stdio(false);
cin.tie(0);
int n;
cin >> n;
vector<long long> h(n), w(n);
map<long long, vector<long long>, greater<long long> > mp;
for (int i = 0; i < n; i++) {
cin >> h[i];
mp[h[i]].push_back(i);
}
for (int i = 0; i < n; i++) {
cin >> w[i];
}
dsu g(n, w);
vector<bool> b(n, false);
long long ans = 0;
for (auto& p : mp) {
for (auto& x : p.second) {
b[x] = true;
if (x > 0 && b[x - 1] && !g.same_set(x, x - 1)) {
ans = ((ans - f(p.first, g.st_sz(x - 1))) % MOD + MOD) % MOD;
g.connect(x, x - 1);
}
if (x < n - 1 && b[x + 1] && !g.same_set(x, x + 1)) {
ans = ((ans - f(p.first, g.st_sz(x + 1))) % MOD + MOD) % MOD;
g.connect(x, x + 1);
}
ans = (ans + f(p.first, g.st_sz(x))) % MOD;
}
}
cout << ans << '\n';
return 0;
}
