#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;

}
