#include<stdio.h>

int main(){

  int n, q, sum, i;
  int S[10000], T[500];
  sum = 0;

  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(S[i] == T[j]){
        sum++;
      }
    }
  }

  printf("%d\n", sum);

  return 0;
}
  