#include<bits/stdc++.h>
#define ll long long
using namespace std;
int main(){
	int n;
	cin >> n;
	string a[10005],b[10005],c[10005],d[10005];
	map<string,int>t,w;
	set<string>p1,p2;
	for(int i=0;i<n;i++){
		cin >> a[i] >> b[i] >> c[i] >> d[i];
		t[a[i]]++;
		w[d[i]]++;
	}
	
	return 0;
}