#include <iostream>
#include <cstring>
#include <algorithm>
using namespace std;
// dfs 60分

const int N = 10000;
int n, m;
int h[N], e[N], ne[N], idx, res;
bool visited[N][N];

void add(int a, int b)
{
    e[idx] = b;
    ne[idx] = h[a];
    h[a] = idx++;
}

void dfs(int root, int cur)
{
    visited[root][cur] = true;
    for (int i = h[cur]; ~i; i = ne[i])
    {
        int neighbor = e[i];
        if (visited[root][neighbor])
            continue;
        dfs(root, neighbor);
    }
}

int main()
{
    cin >> n >> m;
    memset(h, -1, sizeof h);
    while (m--)
    {
        int a, b;
        cin >> a >> b;
        add(a, b);
    }

    for (int i = 1; i <= n; i++)
    {
        dfs(i, i);
    }

    res = 0;

    for (int i = 1; i <= n; i++)
    {
        for (int j = 1; j < i; j++)
        {
            if (visited[i][j] && visited[j][i])
                res++;
        }
    }
    cout << res << endl;
    return 0;
}