#include <iostream>
#include <bitset>
using namespace std;
#define AUTHOR "HEX9CF"

bitset<1005> bs[1005];

int main()
{
	int n, m;
	int cnt = 0;
	cin >> n >> m;
	int c = n * (n - 1) / 2;
	for (int i = 0; i < m; i++)
	{
		int a, b;
		cin >> a >> b;
		bs[a][b] = 1;
	}
	
	for (int j = 1; j <= n; j++)
	{
		for (int i = 1; i <= n; i++)
		{
			// a > b, b > c
			if (bs[i][j])
			{
				// a > c
				bs[i] |= bs[j];
			}
		}
	}
	for (int i = 1; i <= n; i++)
	{
		cnt += bs[i].count();
		// cout << bs[i].count() << endl;
	}
	// cout << cnt << endl;
	cout << c - cnt << endl;
	return 0;
}