import sys input = sys.stdin.readline class SCC: def __init__(self,n): self.n = n self.edges = [] def csr(self): self.start = [0]*(self.n+1) self.elist = [0]*len(self.edges) for e in self.edges: self.start[e[0]+1] += 1 for i in range(1,self.n+1): self.start[i] += self.start[i-1] counter = self.start[:] for e in self.edges: self.elist[counter[e[0]]] = e[1] counter[e[0]] += 1 def add_edge(self,u,v): self.edges.append((u,v)) def scc_ids(self): self.csr() n = self.n now_ord = group_num = 0 visited = [] low = [0]*n order = [-1]*n ids = [0]*n parent = [-1]*n stack = [] for i in range(n): if order[i] == -1: stack.append(i) stack.append(i) while stack: v = stack.pop() if order[v] == -1: low[v] = order[v] = now_ord now_ord += 1 visited.append(v) for i in range(self.start[v],self.start[v+1]): to = self.elist[i] if order[to] == -1: stack.append(to) stack.append(to) parent[to] = v else: low[v] = min(low[v],order[to]) else: if low[v] == order[v]: while True: u = visited.pop() order[u] = n ids[u] = group_num if u == v: break group_num += 1 if parent[v] != -1: low[parent[v]] = min(low[parent[v]],low[v]) for i,x in enumerate(ids): ids[i] = group_num-1-x return group_num,ids def scc(self): group_num,ids = self.scc_ids() groups = [[] for i in range(group_num)] for i,x in enumerate(ids): groups[x].append(i) return groups class Unionfind: def __init__(self,n): self.uf = [-1]*n def find(self,x): if self.uf[x] < 0: return x else: self.uf[x] = self.find(self.uf[x]) return self.uf[x] def same(self,x,y): return self.find(x) == self.find(y) def union(self,x,y): x = self.find(x) y = self.find(y) if x == y: return False if self.uf[x] > self.uf[y]: x,y = y,x self.uf[x] += self.uf[y] self.uf[y] = x return True def size(self,x): x = self.find(x) return -self.uf[x] n,q = map(int,input().split()) e = [[] for i in range(n)] re = [[] for i in range(n)] mod = 998244353 ans = 1 scc = SCC(n) for i in range(q): a,b,c = map(int,input().split()) a,b = a-1,b-1 scc.add_edge(a,b) e[a].append([b,c]) re[b].append([a,c]) vis = [0]*n id = 0 def search(u,c,id): dic = {} dic[u] = c vis[u] = id q = [u] ok = 1 # print(u,c,dic) while q: now = q.pop() c = dic[now] # print(now,c) for nex,nc in e[now]: if c == 0: judge = nc else: judge = nc^1 # print(now,nex,nc,judge,dic) if nex in dic and dic[nex] != judge: ok = 0 if vis[nex] == id: continue dic[nex] = judge vis[nex] = id q.append(nex) for nex,nc in re[now]: if nc == c: judge = 0 else: judge = 1 if nex in dic and dic[nex] != judge: ok = 0 if vis[nex] == id: continue dic[nex] = judge vis[nex] = id q.append(nex) # print(ok) return ok gr = scc.scc() for g in gr: # print(g) if vis[g[0]]: continue u = g[0] num = search(u,0,id+1) + search(u,1,id+2) ans *= num ans %= mod id += 2 print(ans)