uestc 1511 糖果 差分约束

/*
author:jxy
lang:C/C++
university:China,Xidian University
**If you need to reprint,please indicate the source**
*/
#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <queue>
#define INF 1E9
using namespace std;
int First[100005],Next[200005],W[200005],U[200005];
int cnt;
int N;
void add(int v,int u,int w)
{
Next[cnt]=First[v];
First[v]=cnt;
W[cnt]=w;
U[cnt]=u;
cnt++;
}
int in[100005];
long long Dis[100005];
bool inq[100005];
queue<int> q;
bool spfa()
{
int now,i,u;
long long t;
while(!q.empty())
{
now=q.front();q.pop();
inq[now]=0;
if(in[now]>N)return 1;
for(i=First[now];~i;i=Next[i])
{
u=U[i];
if(Dis[u]<(t=Dis[now]+W[i]))
{
Dis[u]=t;
if(++in[u]>N)return 1;
if(inq[u])continue;
inq[u]=1;
q.push(u);
}
}
}
return 0;
}
inline void inp( int &n )//fast input function
{
n=0;
int ch=getchar_unlocked(),sign=1;
while( ch < '0' || ch > '9' ){if(ch=='-')sign=-1; ch=getchar_unlocked();}
while( ch >= '0' && ch <= '9' )
n=(n<<3)+(n<<1)+ ch-'0', ch=getchar_unlocked();
n=n*sign;
}

int main()
{
int K,i,t,A,B;
scanf("%d%d",&N,&K);
cnt=0;
for(i=1;i<=N;i++)
{
First[i]=-1;
Dis[i]=in[i]=inq[i]=1;
q.push(i);
}
for(i=0;i<K;i++)
{
inp(t);
inp(A);
inp(B);
switch(t)
{
case 1:add(A,B,0);add(B,A,0);break;
case 2:add(A,B,1);
if(A==B)
{
puts("-1");
return 0;
}break;
case 3:add(B,A,0);break;
case 4:add(B,A,1);
if(A==B)
{
puts("-1");
return 0;
}break;
case 5:add(A,B,0);break;
}
}
if(spfa())printf("%d\n",-1);
else
{
long long ans=0;
for(i=1;i<=N;i++)
{
ans+=Dis[i];
//  cout<<Dis[i]<<endl;
}
//cout<<Min<<endl;
printf("%lld\n",ans);
}
}