#include<stdio.h>
/*
2019. 4/26
A Linear Search
*/

int search(int A[], int n, int key){
    int i = 0;
    A[n] = key;
    while(A[n] != 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;
}

