#include <bits/stdc++.h>
#define int long long
using namespace std;
const int MOD = 1e9+7, INV = 250000002;
int f(int n, int m) {
return n * m % MOD * (n + 1) % MOD * (m + 1) % MOD * INV % MOD;
}
signed main() {
//input and sum
int n;
cin >> n;
vector<int> h(n), w(n);
for(int i = 0; i < n; i++) cin >> h[i];
for(int i = 0; i < n; i++) cin >> w[i];
//linearily go over and compute result
int res = 0;
vector<int> hSorted(n+1);
for(int i = 0; i < n; i++) hSorted[i+1] = h[i];
sort(hSorted.begin(), hSorted.end());
for(int i = 0; i < n+1; i++) {
int consecutiveW = 0, minH = INT_MAX;
for(int j = 0; j < n; j++) {
if(h[j] <= hSorted[i]) {
//cout << j << " " << hSorted[i] << " " << minH << " " << consecutiveW << "\n";
res = (res + f(minH, consecutiveW)) % MOD;
if(i != 0) res = (res - f(hSorted[i], consecutiveW)) % MOD;
if(res < 0) res = (res + 10000000070000000) % MOD;
consecutiveW = 0, minH = INT_MAX;
} else {
consecutiveW = (consecutiveW + w[j]) % MOD;
minH = min(minH, h[j]);
}
}
res = (res + f(minH, consecutiveW)) % MOD;
if(i != 0) res = (res - f(hSorted[i], consecutiveW)) % MOD;
if(res < 0) res = (res + 10000000070000000) % MOD;
}
//cout << h[n-1] << " " << m << "\n";
cout << res << "\n";
}
