#include "../../include/aoc.hpp"
#include <bits/stdc++.h>
using namespace std;

int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);

	unordered_set<string> all;
	unordered_map<string, unordered_set<string>> m;

	string line;
	while (getline(cin, line)) {
		string a = line.substr(0, 2);
		string b = line.substr(3, 5);
		all.insert(a);
		all.insert(b);
		m[a].insert(b);
		m[b].insert(a);
	}

	int count = 0;
	vector<string> vm;
	vm.assign(all.begin(), all.end());
	for (int i = 2; i < vm.size(); i++) {
		for (int j = 1; j < i; j++) {
			for (int k = 0; k < j; k++) {
				const string &a = vm[i], &b = vm[j], &c = vm[k];
				if (a[0] != 't' && b[0] != 't' && c[0] != 't') {
					continue;
				}
				if (m[a].contains(b) && m[b].contains(c) && m[c].contains(a)) {
					count++;
				}
			}
		}
	}
	cout << count << '\n';
}