#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;
}
