import java.util.*; import java.io.*; import java.math.*;
public class Main{
	//Don't have to see. start------------------------------------------
	static class InputIterator{
		ArrayList<String> inputLine = new ArrayList<String>(1024);
		int index = 0; int max; String read;
		InputIterator(){
			BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
			try{
				while((read = br.readLine()) != null){
					inputLine.add(read);
				}
			}catch(IOException e){}
			max = inputLine.size();
		}
		boolean hasNext(){return (index < max);}
		String next(){
			if(hasNext()){
				return inputLine.get(index++);
			}else{
				throw new IndexOutOfBoundsException("There is no more input");
			}
		}
	}
	static HashMap<Integer, String> CONVSTR = new HashMap<Integer, String>();
	static InputIterator ii = new InputIterator();//This class cannot be used in reactive problem.
	static PrintWriter out = new PrintWriter(System.out);
	static void flush(){out.flush();}
	static void myout(Object t){out.println(t);}
	static void myerr(Object t){System.err.print("debug:");System.err.println(t);}
	static String next(){return ii.next();}
	static boolean hasNext(){return ii.hasNext();}
	static int nextInt(){return Integer.parseInt(next());}
	static long nextLong(){return Long.parseLong(next());}
	static double nextDouble(){return Double.parseDouble(next());}
	static ArrayList<String> nextStrArray(){return myconv(next(), 8);}
	static ArrayList<String> nextCharArray(){return myconv(next(), 0);}
	static ArrayList<Integer> nextIntArray(){
		ArrayList<String> input = nextStrArray(); ArrayList<Integer> ret = new ArrayList<Integer>(input.size());
		for(int i = 0; i < input.size(); i++){
			ret.add(Integer.parseInt(input.get(i)));
		}
		return ret;
	}
	static ArrayList<Long> nextLongArray(){
		ArrayList<String> input = nextStrArray(); ArrayList<Long> ret = new ArrayList<Long>(input.size());
		for(int i = 0; i < input.size(); i++){
			ret.add(Long.parseLong(input.get(i)));
		}
		return ret;
	}
	static String myconv(Object list, int no){//only join
		String joinString = CONVSTR.get(no);
		if(list instanceof String[]){
			return String.join(joinString, (String[])list);
		}else if(list instanceof ArrayList){
			return String.join(joinString, (ArrayList)list);
		}else{
			throw new ClassCastException("Don't join");
		}
	}
	static ArrayList<String> myconv(String str, int no){//only split
		String splitString = CONVSTR.get(no);
		return new ArrayList<String>(Arrays.asList(str.split(splitString)));
	}
	public static void main(String[] args){
		CONVSTR.put(8, " "); CONVSTR.put(9, "\n"); CONVSTR.put(0, "");
		solve();flush();
	}
	//Don't have to see. end------------------------------------------
  static Node[] alist;
	static void solve(){//Here is the main function
      int N = nextInt();
      alist = new Node[N];
      Node[] blist = new Node[N];
      for(int i = 0; i < N; i++){
        ArrayList<Integer> tmp = nextIntArray();
        alist[i] = new Node(tmp.get(0), tmp.get(1));
      }
      for(int i = 0; i < N; i++){
        ArrayList<Integer> tmp = nextIntArray();
        blist[i] = new Node(tmp.get(0), tmp.get(1));
      }
      for(int i = 0; i < N; i++){
        for(int j = 0; j < N; j++){
          if(alist[j].x < blist[i].x && alist[j].y < blist[i].y){
            blist[i].child.add(j);
          }
        }
        blist[i].thisSort();
      }
      Arrays.sort(blist, new originCompare());
      HashSet<Integer> aused = new HashSet<Integer>();
      for(int i = 0; i < N; i++){
        ArrayList<Integer> child = blist[i].child;
        for(int j = 0; j < child.size(); j++){
          if(!aused.contains(child.get(j))){
            aused.add(child.get(j));
            break;
          }
        }
      }
  
      myout(aused.size());
	}
	//Method addition frame start

static class Node{
  int x;
  int y;
  ArrayList<Integer> child = new ArrayList<Integer>();
  Node(int x, int y){
  	this.x = x;
    this.y = y;
  }
  public void thisSort(){
    Collections.sort(child, new originCompare2());
  }
}
  
static class originCompare implements Comparator<Node>{
  public int compare(Node mae, Node ato){
    return mae.x - ato.x;
  }
}

static class originCompare2 implements Comparator<Integer>{
  public int compare(Integer mae, Integer ato){
    return alist[ato].y - alist[mae].y;
  }
}
  
  
	//Method addition frame end
}


Measured memory_bytes: 33224