#include <bits/stdc++.h>
using namespace std;
#define ll int64_t
#define FOR(I,L,R) for(int I=(L); I<=(R); ++I)
#define FOD(I,R,L) for(int I=(R); I>=(L); --I)
#define fi first
#define se second
const ll N = 2e5+5;
const ll mod = 1e9+7;
ll n;
ll H[N], W[N];
ll pref[N], pref2[N];
ll L[N], R[N];
ll power(ll a, ll b){
ll r=1;
while(b){
if(b&1) r=r*a%mod;
a=a*a%mod;
b>>=1;
}
return r;
}
signed main(){
ios::sync_with_stdio(0);
cin.tie(0);
cin>>n;
FOR(i,1,n) cin>>H[i];
FOR(i,1,n){
cin>>W[i];
pref[i]=(pref[i-1]+W[i])%mod;
}
FOR(i,1,n)
pref2[i]=(pref2[i-1]+pref[i])%mod;
stack<ll> st;
// L[i]
FOR(i,1,n){
while(!st.empty() && H[st.top()]>=H[i])
st.pop();
L[i]= st.empty()?0:st.top();
st.push(i);
}
while(!st.empty()) st.pop();
// R[i]
FOD(i,n,1){
while(!st.empty() && H[st.top()]>H[i])
st.pop();
R[i]= st.empty()?n+1:st.top();
st.push(i);
}
ll inv2=(mod+1)/2;
ll ans=0;
FOR(i,1,n){
ll l=L[i]+1;
ll r=R[i]-1;
// tổng pref từ i→r
ll right_sum = (pref2[r]-pref2[i-1]+mod)%mod;
ll right_cnt = (r-i+1);
// tổng pref từ l-1→i-1
ll left_sum = (pref2[i-1] - (l>=2?pref2[l-2]:0) + mod)%mod;
ll left_cnt = (i-l+1);
ll totalS =
( right_sum*left_cnt%mod
- left_sum*right_cnt%mod
+ mod )%mod;
ll totalS2 = totalS * ((totalS+1)%mod) % mod * inv2 % mod;
ans = (ans + H[i]%mod * totalS2%mod)%mod;
}
cout<<ans;
}
