import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.io.IOException;
import java.util.Scanner;
import java.util.List;
import java.util.ArrayList;
 
public class Main {
    public static void main(String[] args) throws IOException {
         
        Scanner sc = new Scanner(System.in);
        
        int n = sc.nextInt();
        int[] s = new int[n];
        for(int i = 0; i < n; ++i) s[i] = sc.nextInt();
        
        int q = sc.nextInt();
        int[] t = new int[q];
        for(int i = 0; i < q; ++i) t[i] = sc.nextInt();
         
        int cnt = 0;
        for(int p : t)
            if(Arrays.binarySearch(s, p) >= 0) ++cnt;
        
        System.out.println(cnt);
    }
}

/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