#include<stdio.h>

int main(){
    int n, q, i, j, S[10000], T[500], count = 0;
    
    scanf("%d", &n);
    for (i = 0; i < n; i++){
        scanf("%d", &S[i]);
    }
    scanf("%d", &q);
    for (i = 0; i < q; i++){
        scanf("%d", &T[i]);
        for (j = 0; j < n; j++){
            if(T[i] == S[j]){
                count++;
                break;
            }
        }
    }
    
    printf("%d\n", count);
    
    return 0;
}
