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

int main(){
    std::ios::sync_with_stdio(false);
    std::cin.tie(0);
    
    //input
    std::vector<std::pair<int, bool>> len_black;
    int nw;
    std::cin >> nw;
    for(int i=0; i<nw; ++i){
        int w;
        std::cin >> w;
        len_black.push_back(std::make_pair(w, false));
    }
    int nb;
    std::cin >> nb;
    for(int i=0; i<nb; ++i){
        int b;
        std::cin >> b;
        len_black.push_back(std::make_pair(b, true));
    }
    
    //sort
    std::sort(len_black.begin(), len_black.end(), [](const std::pair<int, bool>& l, const std::pair<int, bool>& r){
        return l.first>r.first;
    });
    
    //solve
    int ans = -1;
    for(int color=0; color<2; ++color){
        int tmpAns = 0;
        int readPos;
        int readLen;
        bool colorBlackF = (color==0) ? false : true;
        //search first block
        for(size_t i=0; i<len_black.size(); ++i){
            if(len_black[i].second==colorBlackF){
                readPos=i;
                readLen=len_black[i].first+1;
                break;
            }
        }
        //count putable block
        for(size_t i=readPos; i<len_black.size(); ++i){
            if(len_black[i].second==colorBlackF && len_black[i].first<readLen){
                ++tmpAns;
                colorBlackF=!colorBlackF;
                readLen=len_black[i].first;
            }
        }
        ans = std::max(ans, tmpAns);
    }
    
    //output
    std::cout << ans << "\n";

    return 0;
}