/*
 * ANARC05B.cpp
 *
 *  Created on: Jun 1, 2014
 *      Author: Arpit Bhayani
 */

#include <cstdio>
#include <cstdlib>
#include <iostream>

using namespace std;

#define DEBUG 0

int a[11000], b[11000];

int max(int c, int d) {
    return c > d ? c : d;
}

int main(int argc, char * argv[]) {

    int n, m;
    scanf("%d" , &n);

    while (n != 0) {

        for (int i = 0; i < n; i++)
            scanf("%d" , &a[i]);

        scanf("%d" , &m);
        for (int i = 0; i < m; i++)
            scanf("%d" , &b[i]);

        int suma = 0, sumb = 0, result = 0;
        int i = 0, j = 0;

        while (1) {

            if (i < n && j < m && a[i] < b[j]) {
                suma += a[i];
                //cout << "suma = " << suma << endl;
                i++;
            } else if (i < n && j < m && b[j] < a[i]) {
                sumb += b[j];
                //cout << "sumb = " << sumb << endl;
                j++;
            } else if (i < n && j < m && a[i] == b[j]) {
                result += max(suma + a[i], sumb + b[j]);
                //cout << "result = " << result << endl;
                suma = sumb = 0;
                i++;
                j++;
            }

            if ( i >= n && j >= m )
                break;

            if ( i >= n ) {
                //cout << "adding remaining b" << endl;
                while ( j < m ) {
                    sumb += b[j];
                    j++;
                }
                result += max(suma , sumb);
                break;
            }

            if ( j >= m ) {
                //cout << "adding remaining a" << endl;
                while ( i < n ) {
                    suma += a[i];
                    //cout << "suma = " << suma << endl;
                    i++;
                }
                //cout << " max of : " << suma << " and " << sumb << endl;
                result += max(suma, sumb);
                //cout << "result = " << result << endl;
                break;
            }

        }

        cout << result << endl;

        scanf("%d" , &n);
    }

    return 0;
}