import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.*;

public class Main {
	public static void main(String[] args) {
		ALDS1_4_B();
	}

	public static void ALDS1_4_B() {
		Scanner sc = new Scanner(System.in);
		int ans = 0;
		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[n];
		for(int i = 0; i < q; i++) {
			T[i] = sc.nextInt();
			if(Arrays.binarySearch(S, T[i]) >= 0) {
				ans++;
			}
		}
		System.out.println(ans);
	}
}

/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