#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(void){
    // Your code here!
    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;
}

