import java.util.Scanner;
import java.util.Set;
import java.util.TreeSet;


public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		
		int n = sc.nextInt();
		Set<Integer> T = new TreeSet<Integer>();
		
		for(int i=0;i<n;i++){
			T.add(sc.nextInt());
		}
		int p = sc.nextInt();
		int cnt=0;
		for(int i=0;i<p;i++){
			int t= sc.nextInt();
			if(T.contains(t)){
				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