import std.algorithm, std.array, std.container, std.range;
import std.string, std.conv;
import std.math, std.bigint, std.bitmanip, std.random;
import std.stdio, std.typecons;

void main()
{
  auto nw = readln.chomp.to!int;
  auto wi = readln.split.map!(to!int).array;
  auto nb = readln.chomp.to!int;
  auto bi = readln.split.map!(to!int).array;

  wi.sort!("a > b");
  bi.sort!("a > b");

  writeln(max(calc(wi, bi, 0, 0), calc(bi, wi, 0, 0)));
}

int calc(int[] ai, int[] bi, int prev, int acc)
{
  if (ai.empty) {
    return acc;
  } else if (prev == 0) {
    return calc(bi, ai[1..$], ai.front, acc + 1);
  } else {
    auto ci = ai.find!(x => x < prev);
    if (ci.empty)
      return acc;
    else
      return calc(bi, ci[1..$], ci.front, acc + 1);
  }
}