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

struct Query {
  int length;
  bool type;
  bool operator<(const Query& q) const {
    return(length < q.length);
  }
};

int main()
{
  vector< Query > query;

  for(int i = 0; i < 2; i++) {
    int N;
    cin >> N;
    while(N--) {
      int Digit;
      cin >> Digit;
      query.push_back((Query){Digit, i});
    }
  }
  sort(query.begin(), query.end());
  int height = 0, type = -1, length = -1;
  for(int i = 0; i < query.size(); i++) {
    Query& q = query[i];
    if(type != q.type && length < q.length) {
      height++;
      type = q.type;
      length = q.length;
    }
  }
  cout << height << endl;
}