#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(){
    int n,i,A[100001];
    int 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;
}

