#define _USE_MATH_DEFINES
#include <algorithm>
#include <cstdio>
#include <functional>
#include <iostream>
#include <cfloat>
#include <climits>
#include <cstring>
#include <cmath>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <time.h>
#include <vector>
using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> i_i;
typedef pair<ll, int> ll_i;
typedef pair<double, int> d_i;
typedef pair<ll, ll> ll_ll;
typedef pair<double, double> d_d;
struct edge { int u, v; ll w; };

ll MOD = 1000000007;
ll _MOD = 1000000009;
double EPS = 1e-10;

int main() {
	vector<bool> w(20), b(20);
	int N; cin >> N;
	while (N--) {
		int W; cin >> W;
		w[W - 1] = true;
	}
	cin >> N;
	while (N--) {
		int B; cin >> B;
		b[B - 1] = true;
	}
	int maxi = 0;
	for (int S = 0; S < (1 << 20); S++) {
		int cnt = 0; bool ok = true;
		for (int i = 0; i < 20; i++) {
			if (!(S & (1 << i))) continue;
			if (cnt % 2 == 0 && !w[i]) ok = false;
			if (cnt % 2 == 1 && !b[i]) ok = false;
			cnt++;
		}
		if (ok) maxi = max(maxi, cnt);
	}
	for (int S = 0; S < (1 << 20); S++) {
		int cnt = 0; bool ok = true;
		for (int i = 0; i < 20; i++) {
			if (!(S & (1 << i))) continue;
			if (cnt % 2 == 0 && !b[i]) ok = false;
			if (cnt % 2 == 1 && !w[i]) ok = false;
			cnt++;
		}
		if (ok) maxi = max(maxi, cnt);
	}
	cout << maxi << endl;
}