#include<stdio.h>

int main() {
  int n;
  int A[10000],B[10000],a,b;
  int s;
  int i,j,k=0;

  scanf("%d\n",&n);
  for (i=0; i<n; i++) {
    scanf("%d",&a);
    A[i]=a;
  }
  scanf("%d\n",&s);
  for (i=0; i<s; i++) {
    scanf("%d",&b);
    B[i]=b;
  }

  for (i=0; i<n; i++) {
    for (j=0; j<s; j++) {
      if (A[i]==B[j]) {
        k++;
        break;
      }
    }
  }
  printf("%d\n",k);
  return 0;
}