#include<algorithm>
#include<cstdio>
#include<iostream>
#include<unordered_map> 
using namespace std;
unordered_map<string,int>a;
string x;
int main(){
	int n,m;
	scanf("%d%d",&n,&m);
	for(int i=1;i<=n;++i){
		cin>>x;
		a[x]=1;
	}
	int ans=0;
	for(int i=1;i<=m;++i){
		cin>>x;
		if(a[x])++ans;
	}
	printf("%d\n",ans);
	return 0;
}