#include <bits/stdc++.h>
//#define DEBUG 1106
#define int long long
#define ll long long
#define ld long double
#define pb push_back
#define p_q priority_queue
#define m_p make_pair
#define pii pair<int,int>
#define endl '\n'
#define INIT ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define FOR(i,a,b) for(int i = a; i <= b; i++)
#define forn(i,n) for (int i = 0; i < n; i++)
#define forn1(i,n) for (int i = 1; i <= n; i++)
#define all(x) x.begin(),x.end()
#define ft first
#define sd second
#define lowbit(x) (x&(-x))
#define chmax(x,y) x=max(x,y)
#define chmin(x,y) x=min(x,y)
#ifdef DEBUG
#define debug(x) cout << #x << ": " << x << endl;
#else
#define debug(x) 1106;
#endif
using namespace std;
const int N = 2e5+5;
const int inf = 1e9;
const int INF = 1e18;
const int MOD = 1e9+7;
const int mod = 1e9+7;
int h[N], w[N];
int f(int x) {
return (x*(x+1)/2)%mod;
}
signed main() {
INIT
#ifdef DEBUG
freopen("input.txt", "r", stdin);
#endif
///////////
int n;
cin >> n;
forn(i,n) cin >> h[i];
forn(i,n) cin >> w[i];
int ans = 0;
int sum = 0;
stack<tuple<int,int,int>> st;
forn(i,n) {
ans += f(h[i])*f(w[i]) % mod;
ans %= mod;
int m = 0;
while (st.size() && get<0>(st.top()) >= h[i]){
auto [h,w,p] = st.top();
st.pop();
m += w;
m %= mod;
sum = (sum-p + mod);
sum %= mod;
}
ans += sum*w[i] %mod;
ans %= mod;
ans += m*f(h[i])%mod * w[i]%mod;
ans %= mod;
m += w[i];
m %= mod;
int t = m*f(h[i]);
t %= mod;
sum += t;
sum %= mod;
st.push({h[i], m, t});
}
cout << ans %mod;
}
