6666

#include <bits/stdc++.h>
#define endl "\n"
using namespace std;
int n,a[1001],b[1001],f[1001][1001];
int main(){
	ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
	//freeopen(".in","r",stdin);
	//freeopen(".out","w",stdout);
	cin>>n;
	for(int i=1;i<=n;i++){
		cin>>a[i];
	}
	for(int i=1;i<=n;i++){
		cin>>b[i];
	}
	for(int i=1;i<=n;i++){
		for(int j=1;j<=n;j++){
			if(a[i]==b[j]) f[i][j]=f[i-1][j-1]+1;
			else f[i][j]=max(f[i-1][j],f[i][j-1]);
		}
	}
	cout<<f[n][n];
	return 0;
}