#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 n, q, i, key, A[10000+1], 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;
}

