#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef vector<ll> v;
typedef vector<v> vv;
typedef vector<vv> vvv;
typedef pair<ll,ll> p;
typedef vector<p> vp;
typedef vector<vp> vvp;
typedef vector<vvp> vvvp;
typedef pair<ll, p> tri;
typedef vector<tri> vtri;
typedef vector<vtri> vvtri;
typedef vector<vvtri> vvvtri;
typedef vector<bool> vb;
typedef vector<vb> vvb;
typedef vector<vvb> vvvb;
#define f first
#define s second
#define pb push_back
#define eb emplace_back
#define all(v) (v).begin(),(v).end()
const ll INF = 1e18;
const ll mod = 1e9 + 7;
int main()
{
ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
ll N;
cin >> N;
vp ranges(N);
for (ll i= 0; i < N; i++) cin >> ranges[i].f;
for (ll i = 0; i < N; i++) cin >> ranges[i].s;
v leftGeq(N, -1), rightG(N, N);
stack<p> s;
for (ll i = 0; i < N; i++)
{
while (!s.empty() && s.top().f > ranges[i].f) s.pop();
if (!s.empty()) leftGeq[i] = s.top().s;
s.emplace(ranges[i].f, i);
}
s = stack<p>();
for (ll i = N - 1; i >= 0; i--)
{
while (!s.empty() && s.top().f >= ranges[i].f) s.pop();
if (!s.empty()) rightG[i] = s.top().s;
s.emplace(ranges[i].f, i);
}
v widthPref(N + 1, 0);
for (ll i = 1; i <= N; i++) widthPref[i] = (widthPref[i - 1] + ranges[i - 1].s) % mod;
ll res = 0;
for (ll i = 0; i < N; i++)
{
ll leftCnt = (widthPref[i] - widthPref[leftGeq[i] + 1] + mod) % mod;
ll rightCnt = (widthPref[rightG[i]] - widthPref[i + 1] + mod) % mod;
ll meCnt = ranges[i].s;
ll intervalCnt = ((leftCnt * rightCnt) % mod) + (((meCnt * (meCnt + 1)) / 2) % mod) + (((leftCnt + rightCnt) * meCnt) % mod);
intervalCnt %= mod;
ll heightCnt = ranges[i].f * (ranges[i].f + 1) / 2; heightCnt %= mod;
res += (intervalCnt * heightCnt) % mod;
res %= mod;
}
cout << res << "\n";
return 0;
}
