#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;
}

