// No.110 しましまピラミッド
// https://yukicoder.me/problems/no/110
//

#include <iostream>
#include <vector>
#include <algorithm>
#include <utility>
using namespace std;

int solve(vector<int> w_blocks, vector<int> b_blocks);


int main() {
    std::cin.tie(nullptr);
    std::ios::sync_with_stdio(false);

    unsigned int nw;
    cin >> nw;
    vector<int> w_blocks(nw);
    for (auto i = 0; i < nw; ++i)
        cin >> w_blocks[i];

    unsigned int nb;
    cin >> nb;
    vector<int> b_blocks(nb);
    for (auto i = 0; i < nb; ++i)
        cin >> b_blocks[i];

    int ans = solve(w_blocks, b_blocks);
    cout << ans << endl;
}

int solve(vector<int> w_blocks, vector<int> b_blocks) {
    w_blocks.push_back(-1);
    b_blocks.push_back(-1);
    sort(w_blocks.begin(), w_blocks.end());
    sort(b_blocks.begin(), b_blocks.end());

    const int WHITE = 0;
    const int BLACK = 1;
    vector<vector<int>> blocks(2);
    blocks[WHITE] = move(w_blocks);
    blocks[BLACK] = move(b_blocks);

    // 白いブロックを土台にする場合
    vector<int> ans_w;
    ans_w.push_back(blocks[WHITE][blocks[WHITE].size()-1]);
    int next_block = BLACK;
    while (true) {
        auto p = lower_bound(blocks[next_block].begin(), blocks[next_block].end(), ans_w[ans_w.size()-1]);
        if (*(p-1) == -1)
            break;
        ans_w.push_back(*(p-1));
        next_block = next_block == BLACK? WHITE: BLACK;
    }

    // 黒いブロックを土台にする場合
    vector<int> ans_b;
    ans_b.push_back(blocks[BLACK][blocks[BLACK].size()-1]);
    next_block = WHITE;
    while (true) {
        auto p = lower_bound(blocks[next_block].begin(), blocks[next_block].end(), ans_b[ans_b.size()-1]);
        if (*(p-1) == -1)
            break;
        ans_b.push_back(*(p-1));
        next_block = next_block == BLACK? WHITE: BLACK;
    }

    return max(ans_w.size(), ans_b.size());
}