#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cmath>
#include <utility>
#include <vector>
#include <stack>
#include <queue>
#include <cstring>
#include <set>
#include <map>
using namespace std;
#define fio() ios_base::sync_with_stdio(false); cin.tie(NULL);
#define debug(x) cout << x << " ABC " << endl
#define int long long
#define pb push_back
#define all(v) v.begin(), v.end()
#define F first
#define S second
const int INF = 1e18;
const int MOD = 1e9 + 7;
int gauss(int x){
return (x * (x + 1)) / 2;
}
struct SegTree{
int n;
vector<int> tree;
SegTree(vector<int> &a){
n = a.size() - 10;
tree.assign(4 * n + 100, INF);
build(1, 1, n, a);
}
void build(int node, int tl, int tr, vector<int> &a){
if(tl == tr){
tree[node] = a[tl];
return;
}
int tm = (tl + tr) / 2;
build(node * 2, tl, tm, a);
build(node * 2 + 1, tm + 1, tr, a);
tree[node] = min(tree[node*2], tree[node*2+1]);
}
int query(int node, int l, int r, int tl, int tr){
if(r < tl || tr < l) return INF;
if(l <= tl && tr <= r) return tree[node];
int tm = (tl + tr) / 2;
return min(query(node * 2, l, r, tl, tm), query(node * 2 + 1, l, r, tm + 1, tr));
}
};
void _(){
int n;
cin >> n;
vector<int> h(n+10), w(n+10);
for(int i = 1; i <= n; i++) cin >> h[i];
for(int i = 1; i <= n; i++) cin >> w[i];
SegTree st(h);
int ans = 0;
for(int i = 1; i <= n; i++){
for(int j = i; j <= n; j++){
if(i == j){
int inc = (gauss(h[i]) * gauss(w[i]));
inc = inc % MOD;
ans = (ans + inc);
ans = ans % MOD;
}
else{
int sm = st.query(1, 1, n, i, j);
sm = gauss(sm);
sm = sm * w[i];
sm = sm % MOD;
sm = sm * w[j];
sm = sm % MOD;
ans += sm;
}
}
}
cout << ans << endl;
}
int32_t main(){
fio()
int tc = 1;
//cin >> tc;
while(tc--) _();
return 0;
}
