import java.io.*;
import java.util.Arrays;
import java.util.*;

class Main{
	public static void main(String[] args) throws IOException{
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int n = Integer.parseInt(br.readLine());
		Deque<Integer> stack = new ArrayDeque<Integer>();
		String[] str = (br.readLine()).split(" ");
		int count = 0;
		for (int i = 0 ; i<n ; i++ ) {
			stack.addLast(Integer.parseInt(str[i]));
		}
		int q = Integer.parseInt(br.readLine());
		String[] st = (br.readLine()).split(" ");
		int[] num = new int[q];
		for (int i = 0; i<q ; i++ ) {
			num[i] = Integer.parseInt(st[i]);
		}

		Arrays.sort(num);

		int a;
		try{

			for (int i = 0; i<q ; i++ ) {
				while((a = stack.pollFirst()) < num[i]);
				if (num[i] == a) {
					count++;	
				}else{

					stack.addFirst(a);
					continue;
				}
			}
		}catch (NullPointerException e){

		}

		System.out.println(count);
	}

}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz