#include<bits/stdc++.h>
using namespace std;
#define foru(i,a,b) for(int i=(a); i<=(b); ++i)
#define ford(i,a,b) for(int i=(a); i>=(b); --i)
#define rep(i,a) for(int i=0; i<(a); ++i)
#define sz(a) (int)(a).size()
#define all(a) (a).begin(),(a).end()
#define bit(s,i) (((s)>>(i))&1)
#define ii pair<int,int>
#define fi first
#define se second
#define pb push_back
#define eb emplace_back
#define ll long long
#define _ << " " <<
template <class X, class Y> bool maxi(X &x, Y y){return x<y?x=y,true:false;}
template <class X, class Y> bool mini(X &x, Y y){return x>y?x=y,true:false;}
const int N=1e5+5;
const int mod=1e9+7;
int n,h[N],w[N],l[N],r[N],pw[N];
int div2(int x){
if(x%2==0) return x/2;
return (x+mod)/2;
}
int choose(int x){
return (div2(1LL*x*(x-1)%mod) + x) % mod;
}
int calc(int hh, int w1, int w2, int w3){
return 1LL*choose(hh)*((1LL*w1*(w2+w3)%mod + 1LL*w2*w3%mod + choose(w2))%mod) % mod;
}
void solve(){
cin>>n;
foru(i,1,n) cin>>h[i];
foru(i,1,n) cin>>w[i];
foru(i,1,n){
l[i]=i-1;
while(l[i]>0 && h[l[i]]>h[i]) l[i]=l[l[i]];
}
ford(i,n,1){
r[i]=i+1;
while(r[i]<=n && h[r[i]]>=h[i]) r[i]=r[r[i]];
}
foru(i,1,n){
pw[i]=(pw[i-1]+w[i]) % mod;
}
int res=0;
foru(i,1,n){
int w1=(pw[i-1]-pw[l[i]]+mod)%mod,
w2=w[i],
w3=(pw[r[i]-1]-pw[i]+mod)%mod;
// cout<<w1 _ w2 _ w3 _ calc(h[i],w1,w2,w3)<<'\n';
res=(res + calc(h[i],w1,w2,w3) + mod) % mod;
}
cout<<res<<'\n';
}
int32_t main(){
#define task "test"
if(fopen(task".inp","r")){
freopen(task".inp","r",stdin);
freopen(task".out","w",stdout);
}
cin.tie(0)->sync_with_stdio(0);
int tc=1; //cin>>tc;
rep(i,tc){
solve();
}
}
