#include <stdio.h>

int search(int *, int, int);

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;
}

int search(int A[], int n, int key){
  int i=0;
  A[n] = key;
  while(A[i] != key) i++;
  return i != n;
}

