#include <bits/stdc++.h>
using namespace std;
#define for_(i, s, e) for (int i = s; i < (int) e; i++)
#define for__(i, s, e) for (ll i = s; i < e; i++)
typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> ii;
#define endl '\n'
int main() {
#ifdef shiven
freopen("test.in", "r", stdin);
#endif
ios_base::sync_with_stdio(false);
cin.tie(0);
int n; cin >> n;
vi adv(n), a(n), b(n);
for_(i, 0, n) cin >> adv[i];
for_(i, 0, n) cin >> a[i];
for_(i, 0, n) cin >> b[i];
sort(a.begin(), a.end()); sort(b.begin(), b.end());
int ptb = 0, ans = 0;
for_(pta, 0, n) {
while (ptb < n and b[ptb] < a[pta]) ptb++;
if (ptb == n) break;
ans += 1; ptb++;
}
cout << ans << endl;
return 0;
}
