#pragma gcc optimize("Ofast")
#include <bits/stdc++.h>
using namespace std;

int main() {
    ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);
    int n, m; cin >> n >> m;
    vector<vector<pair<int, int>>> G(n + 1);
    vector<pair<int, int>> E(m);
    vector<int> sp(n + 1);
    sp[0] = 2;
    for (int i = 0; i < m; ++i) {
        int u, v, c; cin >> u >> v >> c;
        E[i] = {u, v};
        G[u].emplace_back(-c, i);
        if (c == 1) G[v].emplace_back(-c, i);
        else sp[u] = -1;
    }
    for (int i = 1; i <= n; ++i) sort(G[i].begin(), G[i].end());
    vector<int> p(n + 1);
    for (int i = 1; i <= n; ++i) p[i] = i;
    sort(p.begin(), p.end(), [&] (const int& x, const int& y) { return sp[x] < sp[y]; });
    int ans = 0;
    vector<int> vis(n + 1), stk(n + 1), evis(m);
    function<void(int)> dfs = [&] (int u) {
        vis[u] = stk[u] = 1;
        for (auto& [c, i] : G[u]) {
            if (evis[i]) continue;
            int v = u != E[i].first ? E[i].first : E[i].second;
            if (vis[v] && stk[v]) ans = 1;
            if (!vis[v]) {
                evis[i] = 1;
                dfs(v);
            }
        }
        stk[u] = 0;
    };
    for (auto o : p)
        if (!vis[o] && o) dfs(o);
    cout << (ans ? "Yes" : "No") << '\n';
}