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

int solve(vector<int>&a,vector<int>&b){
	int ans=0;
	for(int i=0,j=0,bb=21;i<a.size()&&j<b.size();++i){
		if(a.at(i)>=bb)continue;
		++ans;
		while(j<b.size()&&a.at(i)<=b.at(j))++j;
		if(j<b.size())++ans,bb=b.at(j);
	}
	return ans;
}

int main(){
	cin.tie(0),ios::sync_with_stdio(false);
	int nw; cin>>nw;
	vector<int>w(nw); for(auto&&i:w)cin>>i;
	int nb; cin>>nb;
	vector<int>b(nb); for(auto&&i:b)cin>>i;
	sort(w.rbegin(),w.rend()); sort(b.rbegin(),b.rend());
	cout<<max(solve(w,b),solve(b,w))<<"\n"s;
}