#include <bits/stdc++.h> using namespace std; #define ll long long #define ar array const int mxN = 1000; int n, m, p[mxN], sz[mxN]; bool edge[mxN][mxN]; int main() { ios::sync_with_stdio(0); cin.tie(0); cin >> n >> m; for (int i = 0; i < m; ++i) { int a, b; cin >> a >> b, --a, --b; edge[a][b] = 1; bool g = 1; while(g) { g = 0; for (int x = 0; x < n; ++x) for (int y = 0; y < n; ++y) for (int z = 0; z < n; ++z) { if (x == y || x == z || y == z || !edge[x][y] || !edge[y][z] || !edge[z][y] || edge[x][z]) continue; edge[x][z] = 1; g = 1; } } int ans = 0; for (int i = 0; i < n; ++i) ans += count(edge[i], edge[i] + n, 1); cout << ans << "\n"; } return 0; }