/**********************GOD**********************/
#include <iostream>
#include <algorithm>
#include <cmath>
#include <iomanip>
#include <cstdlib>
#include <string>
#include <vector>
#include <set>
#include <queue>
#include <stack>
#include <iterator>
#include <map>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<ll , ll> pll;
#define len length()
#define MP make_pair
#define fs first
#define sc second
#define pb push_back
#define all(x) x.begin() , x.end()
#define kill(x) cout << x , exit(0)
const ll mod = 1e9 + 7;
const int MXN = 2e5 + 4;
ll n, ans;
ll h[MXN], w[MXN], ps[MXN];
ll l[MXN], r[MXN];
ll C(ll x)
{
ll y = x * (x - 1) / 2;
return y % mod;
}
ll Sm(ll a, ll b)
{
return (ps[b] - ps[a] + mod) % mod;
}
int main()
{
ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> n;
for(ll i = 1; i <= n; i ++)
cin >> h[i];
for(ll i = 1; i <= n; i ++) {
cin >> w[i];
ps[i] = (ps[i - 1] + w[i]) % mod;
}
ps[n + 1] = ps[n];
stack<ll> cnd; cnd.push(0);
for(ll i = 1; i <= n; i ++) {
while(cnd.size() && h[i] < h[cnd.top()])
cnd.pop();
if(cnd.size())
l[i] = cnd.top();
cnd.push(i);
}
stack<ll> cdn; cdn.push(0);
for(ll i = n; i > 0; i --) {
while(cdn.size() && h[i] <= h[cdn.top()])
cdn.pop();
if(cdn.size())
r[i] = cdn.top();
cdn.push(i);
}
for(ll i = 1; i <= n; i ++)
if(!r[i])
r[i] = n + 1;
for(ll i = 1; i <= n; i ++) {
ll hs = C(h[i] + 1);
ll x = (Sm(i, r[i] - 1) + 1) % mod;
ll y = (Sm(l[i], i - 1) + 1) % mod;
ll tmp = x * y % mod;
ll z = (w[i] - 1) * x % mod;
ll t = (w[i] - 1) * y % mod;
ll o = C(w[i] - 1);
tmp = (tmp + z + t + o) % mod;
ans = (ans + tmp * hs % mod) % mod;
//cout << i << ' ' << x << '\n';
}
cout << ans;
return 0;
}
/*!
ahkh
*/
