#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 + 1], 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))sum++;
    }
    printf("%d\n", sum);
    return 0;
}

