#include <stdio.h>

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;
}

// 線形探索
int search(int A[], int n, int key) {
    int i = 0;
    A[n] = key;
    while ( A[i] != key ) i++;
    return i != n;
}
