#include<bits/stdc++.h>
#define int long long
using namespace std;
const int N=5e6+5;
struct node{
	int to;
	int dis;
};
vector<node>a[N];
int n,m;
int dis[N],cnt[N];
bool vis[N];
queue<int>q;
int ans;
void spfa(){
	while(!q.empty()){
		int x=q.front();
		vis[x]=0;
		cnt[x]=0;
		q.pop();
		for(int i=0;i<a[x].size();i++){
			int v=a[x][i].to;
			int w=a[x][i].dis;
			if(dis[v]<dis[x]+w){
				ans-=dis[v];
				dis[v]=dis[x]+w;
				ans+=dis[x]+w;
				if(!vis[v]){
					if(++cnt[v]>n){
						printf("-1");
						exit(1);
					}
					vis[v]=1;
					q.push(v);
				}
			}
		}
	}
}
signed main(){
	scanf("%lld%lld",&n,&m);
	int flag=0;
	while(m--){
		int x;
		int u,v;
		scanf("%lld%lld%lld",&x,&u,&v);
		if(x==1){
			a[u].push_back(node{v,0});
			a[v].push_back(node{u,0});
		}
		else if(x==2){
			a[u].push_back(node{v,1});
		}
		else if(x==3){
			a[v].push_back(node{u,0});
		}
		else if(x==4){
			a[v].push_back(node{u,1});
		}
		else{
			a[u].push_back(node{v,0});
		}
		if((x==2||x==4)&&u==v){
			printf("-1");
			return 0;
		}
	}

	if(flag)printf("-1");
	else{
		q.push(0);
		for(int i=1;i<=n;i++){
			a[0].push_back(node{i,0});
			q.push(i);
			vis[i]=1;
			dis[i]=1;
		}
		ans=n;
		spfa();
		printf("%lld",ans);
	}
}

这是代码

TLE了一个点