/* -*- coding: utf-8 -*-
 *
 * 110.cc: No.110 しましまピラミッド - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

const int MAX_N = 10;
const int INF = 1 << 30;

/* typedef */

/* global variables */

int ns[2], as[2][MAX_N];

/* subroutines */

/* main */

int main() {
  for (int i = 0; i < 2; i++) {
    cin >> ns[i];
    for (int j = 0; j < ns[i]; j++) cin >> as[i][j];
    sort(as[i], as[i] + ns[i], greater<int>());
  }

  int maxd = 0;

  for (int st = 0; st < 2; st++) {
    int d = 1;
    int cl = as[st][0], cur = st ^ 1, ci[2];
    ci[st] = 1, ci[cur] = 0;

    for (;;) {
      while (ci[cur] < ns[cur] && as[cur][ci[cur]] >= cl) ci[cur]++;
      if (ci[cur] >= ns[cur]) break;
      d++;
      cl = as[cur][ci[cur]];
      cur ^= 1;
    }

    if (maxd < d) maxd = d;
  }

  printf("%d\n", maxd);
  return 0;
}