#include<stdio.h>
int main (void){
  int i, j, n, q, c = 0;
  int s[10000], t[500];
  scanf ("%d",&n);
  for(i = 0;i < n;i++)
    scanf ("%d",&s[i]);
  scanf ("%d",&q);
  for(i = 0;i < q;i++)
    scanf ("%d",&t[i]);
  for(i = 0;i < q;i++){
    for(j = 0;j < n;j++){
      if(t[i]==s[j])
        c++;
  }}
  printf("%d\n",c);
  return 0;
}