#include <stdio.h>
int fine(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(fine(A, n, key) ) sum++;
    }
    printf("%d\n", sum );
    return 0;
}
