/**
 *   @FileName	a.cpp
 *   @Author	kanpurin
 *   @Created	2020.11.06 22:53:19
**/

#include "bits/stdc++.h" 
using namespace std; 
typedef long long ll;

int main() {
    int n;cin >> n;
    vector<int> a(n),b(n);
    for (int i = 0; i < n; i++) {
        cin >> a[i];
    }
    for (int i = 0; i < n; i++) {
        cin >> b[i];
    }
    sort(a.begin(), a.end());
    ll ans = 0;
    for (int i = 0; i < n; i++) {
        ans += min(n-i,(int)(a.end() - upper_bound(a.begin(), a.end(), b[i])));
    }
    cout << ans << endl;
    return 0;
}