#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;
}
