#include<stdio.h>

int linersearch(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[10001],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(linersearch(A,n,key)) sum++;
    }
    printf("%d\n",sum);
    
    return 0;
}
