import math._

object Main {

  def calc(len: Int, xs: List[Int], ys: List[Int]): Int = {
    if (xs.isEmpty) 0
    else if (len > xs.head) 1 + calc(xs.head, ys, xs.tail)
    else calc(len, xs.tail, ys)
  }

  def main(args: Array[String]) {
    val sc = new java.util.Scanner(System.in)
    val nw = sc.nextInt
    val ws = Array.fill(nw)(sc.nextInt).sorted.reverse.toList
    val nb = sc.nextInt
    val bs = Array.fill(nb)(sc.nextInt).sorted.reverse.toList

    val len = Integer.MAX_VALUE
    val ans = max(calc(len, ws, bs), calc(len, bs, ws))
    println(ans)
  }
}