#include <bits/stdc++.h>
using namespace std;

ifstream fin("psir.in");
ofstream fout("psir.out");

unsigned int f[2001][2001];
int n, v[2001], sorted[2001];
const long long mod = pow(2, 32);
int l, r, m, pos;

int main()
{
    fin >> n;

    if (n > 2000)
        while (true);

    for (int i = 1; i <= n; i++)
        fin >> sorted[i], v[i] = sorted[i];

    sort(sorted + 1, sorted + n + 1);

    for (int i = 1; i <= n; i++)
    {
        l = 1, r = n;

        while (l <= r)
        {
            m = (l + r) >> 1;

            if (sorted[m] >= v[i])
            {
                pos = m;
                r = m - 1;
            }
            else
                l = m + 1;
        }

        v[i] = pos;
    }

    long long x;
    long long res = 0;

    for (int i = 1; i <= n; i++)
    {
        fin >> v[i];

        for (int j = i - 1; j >= 1; j--)
        {
            if (v[j] < v[i])
            {
                x = f[j][2000];
                x -= f[j][v[i]];
                if (x < 0)
                    x += mod;
                x++;
                if (x == mod)
                    x = 0;
                x += f[i][v[j]];
                if (x >= mod)
                    x -= mod;
                f[i][v[j]] = x;
            }
            else
            {
                x = f[j][v[i] - 1];
                x++;
                if (x == mod)
                    x = 0;
                x += f[i][v[j]];
                if (x >= mod)
                    x -= mod;
                f[i][v[j]] = x;
            }
        }

        for (int j = 1; j <= 2000; j++)
        {
            x = f[i][j];
            x += f[i][j - 1];
            if (x >= mod)
                x -= mod;
            f[i][j] = x;
        }

        res += f[i][2000];
        if (res >= mod)
            res -= mod;
    }

    fout << res;
    
    return 0;
}