#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;
}

