#include <bits/stdc++.h>
#define int long long
#define pb push_back
#define fs first
#define sc second
using namespace std;
const int MOD = 1e9 + 7, N = 1e5 + 5;
int h[N], w[N], par[N], len[N], cur, ans;
bool act[N];
int cnt(int x){
return (x * (x + 1) / 2) % MOD;
}
int get(int u){
if(u == par[u]) return u;
else return par[u] = get(par[u]);
}
void unite(int a, int b){
a = get(a), b = get(b);
if(a == b) return;
cur = (cur - cnt(len[a]) - cnt(len[b])) % MOD;
if(cur < 0) cur += MOD;
par[b] = a;
len[a] = (len[a] + len[b]) % MOD;
cur = (cur + cnt(len[a])) % MOD;
}
signed main() {
int n;
cin >> n;
for(int i = 0; i < n; i++) cin >> h[i];
for(int i = 0; i < n; i++) cin >> w[i];
vector<pair<int, int>> v;
for(int i = 0; i < n; i++) v.pb({h[i], i});
sort(v.begin(), v.end());
reverse(v.begin(), v.end());
int i = 0;
while(i < n){
int j = i, H = v[i].fs;
while(j < n and v[j].fs == H) j++;
for(int k = i; k < j; k++){
int id = v[k].sc;
act[id] = 1;
par[id] = id;
len[id] = w[id] % MOD;
cur = (cur + cnt(len[id])) % MOD;
}
for(int k = i; k < j; k++){
int id = v[k].sc;
if(id > 0 and act[id - 1]) unite(id, id - 1);
if(id + 1 < n and act[id + 1]) unite(id, id + 1);
}
int nxt = (j < n ? v[j].fs : 0);
int add = (cnt(H) - cnt(nxt)) % MOD;
if(add < 0) add += MOD;
ans = (ans + cur * add) % MOD;
i = j;
}
cout << ans % MOD << endl;
}
