#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,A[10001],key,sum=0,n,m;

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

    scanf("%d",&m);

    for(i = 0; i < m; i++) {
        scanf("%d",&key);
        if(search(A ,n ,key)) sum ++;
    }
    printf("%d\n",sum);
    return 0;

}