hdu 1317 spfa判环求最长路

一个点入队列次数超过点的总和存在环

#include <stdio.h>
#include <stdlib.h>
#include<map>
#include<algorithm>
#include<string.h>
#include<string>
#include<queue>
using namespace std;
vector<int>G[300];
int book[300],val[300],dis[300],time[300];
#define inf 0x3f3f3f
int spfa(int n)
{
memset(book,0,sizeof(book));
memset(dis,-inf,sizeof(dis));
memset(time,0,sizeof(time));
dis[1]=100;
queue<int>q;
q.push(1);
book[1]=1;

while(!q.empty())
{
int f=q.front();
q.pop();
time[f]++;
book[f]=0;
if(time[f]==n)
dis[f]=inf;
if(time[f]>n)
continue;
for(int i=0; i<G[f].size(); i++)
{
if(dis[G[f][i]]<dis[f]+val[G[f][i]]&&dis[f]+val[G[f][i]]>0)
{
dis[G[f][i]]=dis[f]+val[G[f][i]];

if(G[f][i]==n)
return 1;
if(!book[G[f][i]])
{
book[G[f][i]]=1;
q.push(G[f][i]);
}
}
}
}
return 0;
}
int main()
{
int n;
while(~scanf("%d",&n)&&n!=-1)
{
for(int i=1; i<=n; i++)
{ //printf("ok");
scanf("%d",&val[i]);
int m;
scanf("%d",&m);
for(int j=0; j<m; j++)
{
int v;
scanf("%d",&v);
G[i].push_back(v);
}
}

if(spfa(n))
printf("winnable\n");
else printf("hopeless\n");
for(int i=0;i<=n;i++)
G[i].clear();
}
}