#include <algorithm>
#include <cmath>
#include <iomanip>
#include <iostream>
#include <map>
#include <set>
#include <stack>
#include <string>
#include <string.h>
#include <vector>
using namespace std;
typedef long long ll;

#define rep(i, init, end) for(ll i = init; i < end; i++)
#define REP(i, init, end) for(ll i = init; i < end + 1; i++)
#define rev(i, end, init) for(ll i = init - 1; i >= end; i--)
#define REV(i, end, init) for(ll i = init; i >= end; i--)
#define PI 3.14159265359
#define EPS 0.0000000001
// #define MOD 1000000007
//cout << std::fixed << std::setprecision(15) << y << endl;


int main(){
    ll N, M;
    cin >> N >> M;

    ll A[N + 1];
    ll B[M + 1];
    rep(i, 1, N + 1){
        cin >> A[i];
    }
    rep(i, 1, M + 1){
        cin >> B[i];
    }

    ll count = 0;
    rep(i, 1, N + 1){
        if(B[A[i]] > 0){
            B[A[i]]--;
        }else{
            count++;
        }
    }

    cout << count << endl;

    return 0;
}