#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;
   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;
}