#include <bits/stdc++.h>
typedef long long ll;
using namespace std;
const ll MOD = 1e9 + 7;
int n, m = 0;
ll h[100002], w[100002];
ll node_h[100002], node_w[100002], ans = 0;
pair<ll, int> srt[100002];
int cmp[100002], nd[100002], cnt = 0;
set<int> graph[100002];
int find(int A) {
while (A != cmp[A]) cmp[A] = cmp[cmp[A]], A = cmp[A];
return A;
}
void onion(int A, int B) {
if (find(A) == find(B)) return;
node_w[nd[find(B)]] += node_w[nd[find(A)]];
if (node_w[nd[find(B)]] >= MOD) node_w[nd[find(B)]] -= MOD;
graph[nd[find(B)]].insert(nd[find(A)]);
nd[find(A)] = nd[find(B)];
cmp[find(A)] = cmp[find(B)];
}
ll c2(ll num) { return num * (num - 1) % MOD * 500000004 % MOD; }
void dfs(int node, ll depth, ll prv = 0) {
ans += c2(node_w[node] + 1) * (c2(depth - prv + 1) + (depth - prv) * prv % MOD) % MOD;
if (ans >= MOD) ans -= MOD;
for (int i : graph[node]) dfs(i, node_h[i], depth);
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cin >> n;
for (int i = 1; i <= n; i++) {
cin >> h[i];
srt[i] = {h[i], i};
}
for (int i = 1; i <= n; i++) cin >> w[i];
sort(srt + 1, srt + n + 1, greater<pair<ll, int>>());
iota(cmp + 1, cmp + n + 1, 1);
for (int i = 1, j = 1; i <= n; i = j) {
while (j <= n && srt[j].first == srt[i].first) j++;
for (int k = i; k < j; k++) {
int x = srt[k].second;
if (k == i || find(x) != find(srt[k - 1].second)) {
nd[x] = ++cnt;
node_h[cnt] = h[x];
node_w[cnt] = w[x];
} else {
node_w[cnt] += w[x];
if (node_w[cnt] >= MOD) node_w[cnt] -= MOD;
}
if (h[x] < h[x + 1]) onion(x + 1, x);
if (h[x] <= h[x - 1]) onion(x - 1, x);
}
}
dfs(cnt, node_h[cnt]);
cout << ans << '\n';
return 0;
}
