#include <bits/stdc++.h>
using namespace std;
#define LL long long
const int N = 1e6 + 10;
struct sentence {
	string start, end;
}a[N];
int n, ans1, ans2;
map<string, int> h1, h2;
vector<string> v;
int main() {
	cin >> n;
	for (int i = 1; i <= n; i++) {
		string t;
		cin >> a[i].start >> t >> t >> a[i].end;
		h1[a[i].start]++;
		h2[a[i].end]++;
		v.push_back(a[i].start);
		v.push_back(a[i].end);
	}
	for (int i = 0; i < v.size(); i++) {
		ans1 += min(h1[v[i]] / 2, h2[v[i]]);
		ans2 += min(h1[v[i]], h2[v[i]] / 2); 
	}
	cout << ans1 / 2 * ans2 / 2 / 2 / 4 << '\n';
	return 0;
}