#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;
}

