#include <iostream>
#include <algorithm>
#include <cstring>
#include <queue>

using namespace std;
const int N = 1010,M = 1e4 + 10;
typedef pair<int,int> PII;
int h[N],e[M],ne[M],idx;
int g[N][N];
queue<PII> q;
int n,m;

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

void bfs(){

    while(q.size()){
        auto t = q.front();
        q.pop();
        int u = t.first,v = t.second;
        for(int i = h[v];i != -1;i = ne[i]){
            int j = e[i];
            if(g[u][j]) continue;
            g[u][j] = 1;
            q.push({u,j});
        }
    }
}

int main(){
    memset(h,-1,sizeof h);
    cin >> n >> m;
    for(int i = 0;i < m;i++){
        int a,b;
        cin >> a >> b;
        add(a,b);
        q.push({a,b});
    }
    bfs();

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