#include <stdio.h>
#define N 100000
#define MD 1000000007
unsigned int X = 12345;
int rand_() {
return (X *= 3) >> 1;
}
int hh[N], ww[N];
void sort(int *ii, int l, int r) {
while (l < r) {
int i = l, j = l, k = r, i_ = ii[l + rand_() % (r - l)], tmp;
while (j < k)
if (hh[ii[j]] == hh[i_])
j++;
else if (hh[ii[j]] > hh[i_]) {
tmp = ii[i], ii[i] = ii[j], ii[j] = tmp;
i++, j++;
} else {
k--;
tmp = ii[j], ii[j] = ii[k], ii[k] = tmp;
}
sort(ii, l, i);
l = k;
}
}
int main() {
static char used[N];
static int ii[N], ll[N], rr[N];
int n, i, ans;
scanf("%d", &n);
for (i = 0; i < n; i++)
scanf("%d", &hh[i]);
for (i = 0; i < n; i++)
scanf("%d", &ww[i]);
for (i = 0; i < n; i++)
ii[i] = i;
sort(ii, 0, n);
ans = 0;
for (i = 0; i < n; i++)
ll[i] = rr[i] = i;
for (i = 0; i < n; i++) {
int i_, h, l, r;
i_ = ii[i], h = (long long) hh[i_] * (hh[i_] + 1) / 2 % MD;
used[i_] = 1, ans = (ans + (long long) ww[i_] * (ww[i_] + 1) / 2 % MD * h) % MD;
l = r = i_;
if (i_ > 0 && used[i_ - 1]) {
l = ll[i_ - 1];
ans = (ans + (long long) ww[l] * ww[i_] % MD * h) % MD, ww[l] = (ww[l] + ww[i_]) % MD;
rr[l] = r, ll[r] = l;
}
if (i_ + 1 < n && used[i_ + 1]) {
r = rr[i_ + 1];
ans = (ans + (long long) ww[l] * ww[i_ + 1] % MD * h) % MD, ww[l] = (ww[l] + ww[i_ + 1]) % MD;
rr[l] = r, ll[r] = l;
}
}
printf("%d\n", ans);
return 0;
}
