#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define all(x) (x).begin(),(x).end()
#define pb push_back
#define fi first
#define se second
#define mp make_pair
#define beg begin
#define siz size()
#define fastio cin.tie(NULL); cout.tie(NULL); ios_base::sync_with_stdio(false);
#define endl '\n'
#define ins insert
#define log LOG
const ll inf = 1e18;
const ll mod = 1e9+7;
const int maxn=1e6+44;
const int log=24;
const int delta=229939;
ll n;
int main(){
fastio
cin>>n;
vector<ll>prefix(n+1);
vector<ll>H(n+1),W(n+1);
ll res=0;
for(ll i=1;i<=n;i++) {
cin>>H[i];
}
for(ll i=1;i<=n;i++) {
cin>>W[i];
prefix[i]=prefix[i-1]+W[i];
}
vector<pair<ll,ll>>v(n);
set<ll>s;
for(ll i=1;i<=n;i++) {
s.insert(i);
v[i-1]=mp(H[i],i);
}
sort(v.rbegin(),v.rend());
s.insert(0);
s.insert(n+1);
for(ll t=0;t<n;t++) {
ll index=v[t].second;
s.erase(index);
auto it= s.upper_bound(index);
ll wd = prefix[*it-1]-prefix[index];
it=prev(it,1);
ll ws = prefix[index-1]-prefix[*it];
wd%=mod;
ws%=mod;
ll w = W[index];
ll h = H[index];
ll sum=h*(h+(ll)1)/(ll)2;
ll sumw=w*(w+(ll)1)/(ll)2;
sum%=mod;
sumw%=mod;
ll toadd=0;
toadd+=(ws*w)%mod;
toadd%=mod;
toadd+=(wd*w)%mod;
toadd%=mod;
toadd+=(wd*ws)%mod;toadd%=mod;
toadd+=sumw;toadd%=mod;
toadd*=sum;toadd%=mod;
res+=toadd;
res%=mod;
}
cout<<res;
}
