import sys input = sys.stdin.readline sys.setrecursionlimit(10**6) class UnionFind(object): def __init__(self, n: int): self.nodes = [-1]*n def find(self, x: int) -> int: if self.nodes[x] < 0: return x else: self.nodes[x] = self.find(self.nodes[x]) return self.nodes[x] def unite(self, x: int, y: int) -> bool: root_x, root_y, nodes = self.find(x), self.find(y), self.nodes if root_x != root_y: if nodes[root_x] > nodes[root_y]: root_x, root_y = root_y, root_x nodes[root_x] += nodes[root_y] nodes[root_y] = root_x return root_x != root_y def scc(N, G, RG): order = [] used = [0]*N group = [None]*N def dfs(s): used[s] = 1 for t in G[s]: if not used[t]: dfs(t) order.append(s) def rdfs(s, col): group[s] = col used[s] = 1 for t in RG[s]: if not used[t]: rdfs(t, col) for i in range(N): if not used[i]: dfs(i) used = [0]*N label = 0 for s in reversed(order): if not used[s]: rdfs(s, label) label += 1 return label, group if __name__ == '__main__': N, M = map(int, input().split()) edges = [] uf = UnionFind(N) for u, v, c in (map(int, input().split()) for _ in range(M)): u -= 1 v -= 1 if c == 1: if not uf.unite(u, v): print('Yes') exit() else: edges.append((u, v)) adj = [set() for _ in range(N)] rev = [set() for _ in range(N)] for u, v in edges: par_u, par_v = uf.find(u), uf.find(v) if par_u == par_v: print('Yes') exit() adj[par_u].add(par_v) rev[par_v].add(par_u) labels, _ = scc(N, adj, rev) if labels < N: print('Yes') else: print('No')