// URL: https://yukicoder.me/problems/no/200

import std.algorithm, std.array, std.container, std.math, std.range, std.typecons, std.string;

version(unittest) {} else
void main()
{
  int N; io.getV(N);
  int A; io.getV(A);
  int[] B; io.getA(A, B);
  int C; io.getV(C);
  int[] D; io.getA(C, D);

  B.sort!"a>b"; D.sort!"a<b";

  auto g = GraphW!int(N*2+2);
  foreach (i; 0..N)
    foreach (j; 0..N) {
      auto ar = i/A, ari = ar*A, ara = (ar+1)*A-1;
      auto cr = j/C, cri = cr*C, cra = (cr+1)*C-1;
      if (cri <= ara && ari <= cra && B[i%A] > D[j%C]) g.addEdge(i, j+N, 1);
    }

  foreach (i; 0..N) {
    g.addEdge(N*2, i, 1);
    g.addEdge(i+N, N*2+1, 1);
  }

  io.put(g.fordFulkerson(N*2, N*2+1).flow);
}

struct Graph
{
  alias Node = int;
  Node n;
  Node[][] g;
  alias g this;
  this(Node n) { this.n = n; g = new Node[][](n); }
  void addEdge(Node u, Node v) { g[u] ~= v; }
  void addEdgeB(Node u, Node v) { g[u] ~= v; g[v] ~= u; }
}

struct GraphW(W = int, W i = 10^^9)
{
  alias Node = int, Wt = W, inf = i;
  struct Edge { Node src, dst; Wt wt; alias cap = wt; }
  Node n;
  Edge[][] g;
  alias g this;
  this(Node n) { this.n = n; g = new Edge[][](n); }
  void addEdge(Node u, Node v, Wt w) { g[u] ~= Edge(u, v, w); }
  void addEdgeB(Node u, Node v, Wt w) { g[u] ~= Edge(u, v, w); g[v] ~= Edge(v, u, w); }
}

struct GraphM(W = int, W i = 10^^9)
{
  alias Node = int, Wt = W, inf = i;
  Node n;
  Wt[][] g;
  alias g this;
  this(int n) { this.n = n; g = new Wt[][](n, n); }
  static GraphM!(W, i) init(Node n)
  {
    auto g = GraphM!(W, i)(n);
    foreach (i; 0..n) { g[i][] = inf; g[i][i] = 0; }
    return g;
  }
}

struct FordFulkerson(Graph)
{
  alias Node = Graph.Node, Wt = Graph.Wt;
  Graph g;
  alias g this;
  Wt flow = 0;

  this(Graph g, Node s, Node t)
  {
    this.g = g;
    auto adj = withRev(), visited = new bool[](n);

    Wt augment(Node u, Wt cur)
    {
      if (u == t) return cur;
      visited[u] = true;
      foreach (ref e; adj[u]) {
        if (!visited[e.dst] && e.cap > e.flow) {
          auto f = augment(e.dst, min(e.cap - e.flow, cur));
          if (f > 0) {
            e.flow += f;
            adj[e.dst][e.rev].flow -= f;
            return f;
          }
        }
      }
      return 0;
    }

    for (;;) {
      visited[] = false;
      auto f = augment(s, g.inf);
      if (f == 0) break;
      flow += f;
    }
  }

  private
  {
    struct EdgeR { Node src, dst; Wt cap, flow; Node rev; }
    EdgeR[][] withRev()
    {
      auto r = new EdgeR[][](n);
      foreach (gi; g)
        foreach (e; gi) {
          r[e.src] ~= EdgeR(e.src, e.dst, e.cap, 0, cast(Node)(r[e.dst].length));
          r[e.dst] ~= EdgeR(e.dst, e.src, 0, 0, cast(Node)(r[e.src].length) - 1);
        }
      return r;
    }
  }
}
FordFulkerson!Graph fordFulkerson(Graph, Node)(Graph g, Node s, Node t)
{
  return FordFulkerson!(Graph)(g, s, t);
}

auto io = IO!()();
import std.stdio;
struct IO(alias IN = stdin, alias OUT = stdout)
{
  import std.conv, std.format, std.meta, std.traits, core.stdc.stdlib;

  auto getV(T...)(ref T v) { foreach (ref w; v) get(w); }
  auto getA(T)(size_t n, ref T v) if (hasAssignableElements!T)
  { v = new T(n); foreach (ref w; v) get(w); }
  auto getC(T...)(size_t n, ref T v)
  if (allSatisfy!(hasAssignableElements, T))
  {
    foreach (ref w; v) w = new typeof(w)(n);
    foreach (i; 0..n) foreach (ref w; v) get(w[i]);
  }
  auto getM(T)(size_t r, size_t c, ref T v)
  if (hasAssignableElements!T && hasAssignableElements!(ElementType!T))
  { v = new T(r); foreach (ref w; v) getA(c, w); }
  template getS(E...)
  {
    auto getS(T)(size_t n, ref T v)
    { v = new T(n); foreach (ref w; v) foreach (e; E) mixin("get(w."~e~");"); }
  }

  const struct PutConf
  {
    bool newline = true, flush, exit;
    string floatFormat = "%.10f", delimiter = " ";
  }

  auto put(alias conf = "{}", T...)(T v)
  { mixin("const PutConf c = "~conf~"; putMain!c(v);"); }
  auto putB(alias conf = "{}", S, T)(bool c, S t, T f)
  { if (c) put(t); else put(f); }
  auto putRaw(T...)(T v) { OUT.write(v); OUT.writeln; }

  private
  {
    dchar[] buf;
    auto sp = (new dchar[](0)).splitter;
    void nextLine() { IN.readln(buf); sp = buf.splitter; }
    auto get(T)(ref T v) { if (sp.empty) nextLine(); v = sp.front.to!T; sp.popFront(); }

    auto putMain(PutConf c, T...)(T v)
    {
      foreach (i, w; v) {
        putOne!c(w);
        if (i < v.length-1) OUT.write(c.delimiter);
      }
      static if (c.newline) OUT.writeln;
      static if (c.flush) OUT.flush();
      static if (c.exit) exit(0);
    }
    auto putOne(PutConf c, T)(T v)
    {
      static if (isInputRange!T && !isSomeString!T) putRange!c(v);
      else if (isFloatingPoint!T) OUT.write(format(c.floatFormat, v));
      else OUT.write(v);
    }
    auto putRange(PutConf c, T)(T v)
    {
      auto w = v;
      while (!w.empty) {
        putOne!c(w.front); w.popFront();
        if (!w.empty) OUT.write(c.delimiter);
      }
    }
  }
}