#include <stdio.h>

int search(int A[], int n, int key)
{
    int i = 0;
    A[n] = key;
    while ( A[i] != key) {
        i++;
    }
    return i != n;
}

int main()
{
    int i, n, A[10000], q, key, sum = 0;
    scanf("%d", &n);
    for ( i = 0; i < n; i++){
        scanf("%d", &A[i]);
    }
    scanf("%d", &q);
    for ( i = 0; i < q; i++){
        scanf("%d", &key);
        if (search(A, n, key) == 1){
            sum++;
        }
    }
    printf("%d\n", sum);
    return 0;
}