NYOJ 1274 信道安全 裸的最短路 spfa 邻接表 第九届省赛C

该比赛了，做一下去年的题

#include 
#include 
#include 
#include 
#include 
using namespace std;
const int INF = 0x3f3f3f;
const int Max = 50005;
struct Node{
	int v,next;
	double w;
}edge[Max<<1];
int head[Max];
bool vis[Max];
double dis[Max];
int n,m,k;
void addedge(int u,int v,double w)
{
	edge[k].v = v;
	edge[k].w = w;
	edge[k].next = head[u];
	head[u] = k++;
}
void spfa(int s)
{
	queueq;
	memset(vis,0,sizeof(vis));
	for(int i = 1; i <= n; i++)
	{
		dis[i] = -INF;
	}
	dis[s] = 1;
	q.push(s);
	while(!q.empty())
	{
		int u = q.front();
		q.pop();
		vis[u] = false;
		for(int i = head[u]; i != -1; i = edge[i].next)
		{
			int v = edge[i].v;
			double w = edge[i].w;
			if(dis[u]*w > dis[v])
			{
				dis[v] = dis[u] * w;
				if(!vis[v])
				{
					vis[v] = true;
					q.push(v);
				}
			}
		}
	}
}
int main()
{
	int T;
	scanf("%d",&T);
	while(T--)
	{
		k = 0;
		memset(head,-1,sizeof(head));
		scanf("%d%d",&n,&m);
		int u,v;
		double w;
		for(int i = 0; i < m; i++)
		{
			scanf("%d%d%lf",&u,&v,&w);
			addedge(u,v,w/100);
			addedge(v,u,w/100);
		}
		spfa(1);
		printf("%.6lf\n",dis[n] * 100);
	}
	return 0;
 }