#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;
}
