#include <bits/stdc++.h>
using namespace std;
bool check (string s1, string s2)
{
	if (s1.size() != s2.size())
	{
		return false;
	}
	for (int i = 0;i < s1.size();i++)
	{
		if (s1[i] != s2[i])
		{
			return false;
		}
	}
	return true;
}
int main()
{
	int n;
	cin >> n;
	getchar();
	string s[n + 1];
	for (int i = 1;i <= n;i++)
	{	
		getline (cin, s[i]);
	}
	string head[n + 1], foot[n + 1];
	for (int i = 1;i <= n;i++)
	{
		for (int j = 0;j < s[i].size();j++)
		{
			if (s[i][j] == ' ')
			{
				string p = "";
				for (int k = j - 1;k >= 0;k--)
				{
					p = s[i][k] + p;
				}
				head[i] = p;
				break;
			}
		}
		for (int j = s[i].size() - 1;j >= 0;j--)
		{
			if (s[i][j] == ' ')
			{
				string p = "";
				for (int k = j + 1;k < s[i].size();k++)
				{
					p += s[i][k];
				}
				foot[i] = p;
				break;		
			}
		}
	}
	int ans = 0;
	for (int i = 1;i <= n;i++)
	{
		int cnt = 0;
		for (int j = 1;j <= n;j++)
		{
			if (head[i] == foot[j])
			{
				++cnt;
			}
		}
		ans += cnt;
	}
	cout << ans / 6;
	return 0;
}