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

public class Main {
	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		
		int n = scanner.nextInt();
		int[] s = new int[n];
		
		for (int i = 0; i < n; i ++) {
			s[i]  = scanner.nextInt();
		}
		
		int q = scanner.nextInt();
		int c = 0;

		for (int i = 0; i < q; i ++) if (Arrays.binarySearch(s, scanner.nextInt()) >= 0) c ++;
		
		scanner.close();
		
		System.out.println(c);
	}
} 


/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