#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(void){
    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;
}