#include <stdio.h>

int L_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(L_search(A, n, key)) sum++;
  }
  printf("%d\n", sum);

  return 0;
}

