#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)

int main() {
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);
    int n, m;
    cin >> n >> m;
    vector<int> a(n);
    vector<int> b(m);
    rep(i, n) cin >> a[i], a[i]--;
    rep(i, m) cin >> b[i];
    rep(i, n) b[a[i]]--;
    int ans = 0;
    rep(i, m) {
        ans -= min(0, b[i]);
    }
    cout << ans << endl;
    return 0;
}