#include <stdio.h>
#include <stdlib.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;
}

