import java.util.*;

public class Main {

    static int NOT_FOUND = 99999999;

    public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int[] sArr = new int[n + 1];
        for (int i = 0; i < n; i++) {
            sArr[i] = sc.nextInt();
        }

        int q = sc.nextInt();
        int[] tArr = new int[q + 1];
        int count = 0;
        for (int i = 0; i < q; i++) {
            int x = sc.nextInt();
            tArr[i] = x;
            if (linearSearch(n, sArr, x) != NOT_FOUND) count++;
        }
        System.out.println(count);
    }

    public static int linearSearch(int n, int[] arr, int key) {
        int i = 0;
        arr[n] = key;
        while (arr[i] != key) {
            i++;
        }
        if (i == n) {
            return NOT_FOUND;
        }
        return i;
    }
}


/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