#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;
}