#include <bits/stdc++.h>
typedef long long ll;
using namespace std;
#define all(x) (x).begin(), (x).end()
#define MOD 1000000007
int main() {
    int nw, nb;
    cin >> nw;
    vector<int> w(nw);
    for(size_t i = 0; i < nw; i++) {
        cin >> w[i];
    }
    cin >> nb;
    vector<int> b(nb);
    for(size_t i = 0; i < nb; i++) {
        cin >> b[i];
    }
    int ans = 0;
    for(int bit = 0; bit < (1 << 20); bit++) {
        int tans = 0;
        int t = bit;
        bool isW = true;
        vector<int> ww = w, bb = b;
        for(int j = 0; j < 20; j++) {
            if(t & 1) {
                if(isW) {
                    auto ex = find(all(ww), j + 1);
                    if(ex != ww.end()) {
                        tans++;
                        isW = false;
                        (*ex) = -1;
                    } else {
                        tans = -114514;
                        break;
                    }
                } else {
                    auto ex = find(all(bb), j + 1);
                    if(ex != bb.end()) {
                        tans++;
                        isW = true;
                        (*ex) = -1;
                    } else {
                        tans = -114514;
                        break;
                    }
                }
            }
            t = t >> 1;
        }
        ans = max(ans, tans);
    }
    for(int bit = 0; bit < (1 << 20); bit++) {
        int tans = 0;
        int t = bit;
        bool isW = false;
        vector<int> ww = w, bb = b;
        for(int j = 0; j < 20; j++) {
            if(t & 1) {
                if(isW) {
                    auto ex = find(all(ww), j + 1);
                    if(ex != ww.end()) {
                        tans++;
                        isW = false;
                        (*ex) = -1;
                    } else {
                        tans = -114514;
                        break;
                    }
                } else {
                    auto ex = find(all(bb), j + 1);
                    if(ex != bb.end()) {
                        tans++;
                        isW = true;
                        (*ex) = -1;
                    } else {
                        tans = -114514;
                        break;
                    }
                }
            }
            t = t >> 1;
        }
        ans = max(ans, tans);
    }
    cout << ans << endl;
}