#include <iostream>
#include <algorithm>
#include <vector>

void solve() {
    std::vector<std::vector<int>> xss(2);
    for (auto& xs : xss) {
        int n;
        std::cin >> n;
        xs.resize(n);

        for (auto& x : xs) std::cin >> x;
        std::sort(xs.begin(), xs.end());
    }

    int ans = 0;
    for (int q = 0; q < 2; ++q) {
        int base = 100, cnt = 0;
        for (int i = 0;; ++i) {
            auto& xs = xss[i % 2];
            auto it = std::lower_bound(xs.begin(), xs.end(), base);

            if (it == xs.begin()) break;
            base = *(--it);
            ++cnt;
        }

        ans = std::max(ans, cnt);

        std::swap(xss[0], xss[1]);
    }

    std::cout << ans << std::endl;
}

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

    solve();

    return 0;
}