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

int main(){
  int n,m;
  cin>>n>>m;
  vector<int> a(n),b(m);
  for (int i=0;i<n;i++) cin>>a[i],a[i]--;
  for (int i=0;i<m;i++) cin>>b[i];
  int ans=n;
  for (int i=0;i<n;i++){
    if (b[a[i]]==0) continue;
    b[a[i]]--;
    ans--;
  }
  cout<<ans<<endl;
}